255639913 has 2 divisors, whose sum is σ = 255639914. Its totient is φ = 255639912.

The previous prime is 255639877. The next prime is 255639983. The reversal of 255639913 is 319936552.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 235100889 + 20539024 = 15333^2 + 4532^2 .

It is a cyclic number.

It is not a de Polignac number, because 255639913 - 2¹³ = 255631721 is a prime.

It is equal to p_13970887 and since 255639913 and 13970887 have the same sum of digits, it is a Honaker prime.

It is a self number, because there is not a number n which added to its sum of digits gives 255639913.

It is not a weakly prime, because it can be changed into another prime (255639983) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 127819956 + 127819957.

It is an arithmetic number, because the mean of its divisors is an integer number (127819957).

Almost surely, 2^255639913 is an apocalyptic number.

It is an amenable number.

255639913 is a deficient number, since it is larger than the sum of its proper divisors (1).

255639913 is an equidigital number, since it uses as much as digits as its factorization.

255639913 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 218700, while the sum is 43.

The square root of 255639913 is about 15988.7433214746. The cubic root of 255639913 is about 634.6625714666.

The spelling of 255639913 in words is "two hundred fifty-five million, six hundred thirty-nine thousand, nine hundred thirteen".