121 = 11 x 11. 121 is the smallest multidigit palindromic square. It is also the smallest palindromic composite such that some permutation...

802 = 2 x 401. 802 is the number of ways to toss a coin 10 times and not get a run of five ( A135492 ). 802 has a representation as a s...

401 is a prime number. 401 is the start of the first occurrence of three consecutive primes using no prime digits: 401 , 409, 419 . 401 ...

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. 783 3 = 480,0...

679 = 7 x 97. 679 is the smallest number with multiplicative persistence 5 ( A003001  and A064869 ). 679 is the sum of three consecut...

494 = 2 x 13 x 19. 494 has the representation 494 = 2 9 - 18. The product of the first 494 composite numbers minus 1 is prime. 494 +...

868 = 2 x 2 x 7 x 31. 4 868 - 3 is a prime number. 868 has a square root whose decimal part starts with the digits 1 to 9 in some order...

396 = 2 x 2 x 3 x 3 x 11. 396 is a nonagonal number . 396 is the number of positions in a 3 x 3 sliding puzzle that require exactly 11 ...

296 = 2 x 2 x 2 x 37. 296 is the number of integer partition s of 30 into distinct parts. 296 has a representation as a sum of two squar...

252 = 2 x 2 x 3 x 3 x 7. 252 is the smallest number that is the product of two distinct numbers that are reverse of each other: 252 = 12 x...

574 = 2 x 7 x 41. 574 is the maximum number of pieces into which a torus can be cut by 14 slices. 574 is 210021 in base 3. It is 707 in ...

759 = 3 x 11 x 23. It is the product of three distinct Sophie Germain primes ( A157346 ). 759 is 1001010 in base 3. It is 3303 in base 6 ...

662 = 2 x 331. 662 is a divisor of 31 3 - 1. 662 is the index of the smallest triangular number that contains the digits 1, 2, 3, 4, a...

753 = 3 x 251. 753 is a divisor of 20 10 - 1. 753 is the smallest composite number that you can get by concatenating all odd primes up ...

139 is a prime number. 137  and 139 form a twin prime pair. 139 is a divisor of 42 3 - 1. 139 is the smallest prime that retains the...

370 = 2 x 5 x 37. 370 is a decagonal number  ( A001107 ). 370 /(3 + 7 + 0) = 37 is prime. 370 = 37 x (3 + 7) = 3 3 + 7 3 . It is an A...

946  = 2 x 11 x 43. 946  is the 43rd  triangular number  ( A000217 ). It is the sum of all integers from 1 to 43. 946  is also a  hexag...

224 = 2 x 2 x 2 x 2 x 2 x 7. 224 has a unique representation as a sum of three squares: 224 = 4 2 + 8 2 + 12 2 . 224 is an abundant nu...

635 = 5 x 127. 635 is a number whose 5th root has a decimal part that begins with 635 (3. 635 42128. . .). 635 4 = 162590400625, a conc...

732 = 2 x 2 x 3 x 61. 732 = 1 7 + 2 6 + 3 5 + 4 4 + 5 3 + 6 2 + 7 1 . 732 = 3 6 + 3. 732 is a divisor of 13 3 - 1. 732 is 44...