4347

4347 = 3 x 3 x 3 x 7 x 23.

4347 is a heptagonal number (A000566). It is also a pentagonal number (A049452).

4347 is the concatenation of the 27th and 28th primes (A045533).

4347 is a value of n for which 2n and 5n together use each of the digits 1 to 9 exactly once.

4347 is the number of regions in a regular 63-gon that are octagons (A067155).

4347 divides 22¹⁸ - 1.

Source: Number Gossip

4774

4774 = 2 x 7 x 11 x 31. It is a palindrome with exactly four prime factors (A046330).

4774 is a heptagonal number (A000566).

4774 is a multiple of 11 and its digit sum is a multiple of 11 (A216995).

4774 is the concatenation of the 15th prime and its reverse (A067087).

4774 is 34034 in base 6 and 2233 in base 13 (A033011).

4774 divides 67³ - 1.

Source: OEIS

1782

1782 = 2 x 3 x 3 x 3 x 3 x 11.

1782 is a heptagonal number.

1782 is the smallest number that is three times the sum of all the two-digit numbers that can be made using the digits of 1782.

1782 is the smallest number n such that n and 4n (7128) are anagrams.

1782 is 3366 in base 8.

1782 divides 89¹⁸ - 1.

Source: Number Gossip

697

697 = 17 x 41.

697 is a heptagonal number.

697 is a cake number.

697 is a 12-hyperperfect number.

697 has two representations as a sum of two squares: 697 = 11² + 24² = 16² + 21².

697 is the hypotenuse of two primitive Pythagorean triples: 697² = 185² + 672² = 455² + 528².

Source: What's Special About This Number? 

616

616 = 2 x 2 x 2 x 7 x 11.

616 is a heptagonal number (A000566). It is also a tridecagonal number (A051865).

616 is a Padovan number (A000931).

616 is 211211 in base 3. It is 434 in base 12 (A029967).

616 is the sum of eight positive fifth powers (A003353).

Source: On-Line Encyclopedia of Integer Sequences

403

403 = 13 x 31. It is the smallest semiprime whose factors form a pair of emirps (13 and 31).

403 is 110010011 in base 2.

403 has a unique representation as a sum of three squares: 403 = 3² + 13² + 15².

403 is a heptagonal number.

403 = 2³ + 3³ + 3³ + 5³ + 6³.

Source: Prime Curios!

783

783 = 3 x 3 x 3 x 29.

783 is a heptagonal number.

783 is the number of 11-ominoes that tile the plane by translation.

783³ = 480,048,687 = (48 + 00 + 48 + 687)³.

783 is 373 in base 15 and 234 in base 19.

Source: What Special About This Number?

1651

1651 = 13 x 127.

1651 is 11001110011 in base 2 (binary) (A048700).

1651 is a heptagonal number (A000566).

1651 is a potential magic constant of a 7 x 7 magic squares composed of consecutive primes (A188536).

1651 is the sum of eight but not fewer squared primes (A183215).

Source: On-Line Encyclopedia of Integer Sequences

970

970 = 2 x 5 x 97.

970 has two representations as a sum of two squares: 970 = 3² + 31² = 21² + 23².

970 is a heptagonal number (A000566).

970 is the number of connected graphs with 8 vertices and 17 edges.

970 is 33022 in base 4 and 12340 in base 5.

The sum of the divisors of 970 is a square (A006532): 1 + 2 + 5 + 10 + 97 + 194 + 485 + 970 = 1764 = 42².

Source: What's Special About This Number?

1177

1177 = 11 x 107.

1177 is a heptagonal number.

1177 is the maximum number of regions into which 48 lines divide the plane.

1177 is a number whose sum of divisors is a fourth power: 1 + 11 + 107 + 1177 = 1296 = 6⁴.

1177 is 414 in base 17.

Source: What's Special About This Number?

286

286 = 2 x 11 x 13.

286 is the 11th tetrahedral number.

286 is a heptagonal number.

286 is the number of rooted trees with 9 vertices.

286 is 2121 in base 5 and 141 in base 15.

286 is the shorthand for the Intel 80286 microprocessor chip.

Source: What's Special About This Number?

342

342 = 2 x 3² x 19.

342 is 666 in base 7. It is the smallest number that can be represented by 666 in any base. 342 is also 2332 in base 5.

342 is a heptagonal number.

342 is the number of inequivalent binary linear codes of length 8.

IC 342 (also known as Caldwell 5) is a spiral galaxy in the constellation Camelopardalis.

Source: Number Gossip

540

540 = 2² x 3³ x 5. All prime divisors are consecutive primes starting at 2.

540 is a heptagonal number and a decagonal number.

540 is divisible by its reverse, 45.

540 is the sum of three distinct positive cubes: 540 = 8³ + 3³ + 1³.

540 is the sum of the internal angles of a five-sided convex polygon (or a pentagon).

Source: What's Special About This Number?

148

148 = 2² x 37.

148 has a representation as a sum of two squares: 148 = 2² + 12².

148 is a heptagonal number. It is also a centered heptagonal number.

148 is the number of perfect graphs with six vertices.

148 x (14 + 8) = 14³ + 8³ = 3256.

Three square numbers using the same digits: 148² = 21904; 203² = 41209; and 302² = 91204.

The astronomical object Arp 148 is the spectacular aftermath of an encounter between two galaxies.

Source: Numeropedia

189

189 = 3³ x 7.

The product of the four primes in a prime quadruplet (except for 5, 7, 11, 13) always ends in 189. Example: 101 x 103 x 107 x 109 = 121,330,189.

189 is a heptagonal number. It is also a centered cube number.

189 is 10111101 in base 2 (binary). It is 99 in base 20 and 90 in base 21.

189 is a divisor of 55² - 1.

The 189th century will be the first to contain as few as five prime years: 18803, 18839, 18859, 18869, and 18899.

Source: Prime Curios!

874

874 = 2 x 19 x 23.

874 is a heptagonal number.

874 is the number of positive integer solutions to (1 + 1/a)(1 + 1/b)(1 + 1/c)(1 + 1/d)(1 + 1/e) = 2.

874 = 0! + 1! + 2! + 3! + 4! + 5! + 6!

874² = 763876 = (7 - 6 - 3 + 876)²

USS Duncan (DDR 874) was a U.S. Navy destroyer, launched in 1945.

Source: What's Special About This Number?

81

81 = 3⁴, a perfect fourth power.

81 is the only integer other than 1 that is the square of the sum of its digits.

81 is a heptagonal number.

81 is a centered octagonal number.

81 = 1 + 3 + 5 + 7 + 9 + 11 + 13 + 15 + 17 (the first nine odd numbers).

The chemical element thallium has the atomic number 81.

Source: Number Gossip

469

469 = 7 x 67.

469 is a heptagonal number. 469 is also a centered hexagonal number.

469 is a value of n for which n! - 1 is a prime number.

469 is the sum of three distinct positive cubes: 469 = 7³ + 5³ + 1³.

Inserting a zero between adjacent digits makes 469 a prime number: 40609.

469 Argentina is a main-belt asteroid discovered in 1901.

Source: What's Special About This Number?

34

34 = 2 x 17.

34 is the ninth Fibonacci number.

34 is the smallest number with the property that it and its neighbors have the same number of divisors (four): 33 = 3 x 11; 34 = 2 x 17; 35 = 5 x 7.

The rows and columns of a 4 x 4 magic square always total 34.

34 has a representation as a sum of two squares: 34 = 3² + 5².

34 is the smallest number with four representations as a sum of two primes: 34 = 3 + 31 = 5 + 29 = 11 + 23 = 17 + 17.

34 is 22 in base 16.

34 is a heptagonal number.


34 is the atomic number of the element selenium.

Source: Number Gossip