2013 is a permutation of the digits 0, 1, 2, and 3 (A203569)
2013, 2014, and 2015 have the same number of divisors (A005238). Each is the product of three distinct primes (A066509 and A113789).
The digital sums of 2013 in base 2 (11111011101), base 3 (2202120), and base 5 (31023) are equal (A135121).
The sum of 2013 and its prime factors equals the sum of 2014 and its prime factors (A020700): 2013 + 3 + 11 + 61 = 2014 + 2 + 19 + 53 = 2088.
2013 is the number of trees with 27 nodes and 4 leaves (A055291).
The year 2013 celebrates the Mathematics of Planet Earth.
2013 is also the International Year of Statistics.
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