256628677 has 2 divisors, whose sum is σ = 256628678. Its totient is φ = 256628676.

The previous prime is 256628663. The next prime is 256628681. The reversal of 256628677 is 776826652.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 244891201 + 11737476 = 15649^2 + 3426^2 .

It is a cyclic number.

It is not a de Polignac number, because 256628677 - 2¹⁹ = 256104389 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 256628677.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (256628657) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128314338 + 128314339.

It is an arithmetic number, because the mean of its divisors is an integer number (128314339).

Almost surely, 2^256628677 is an apocalyptic number.

It is an amenable number.

256628677 is a deficient number, since it is larger than the sum of its proper divisors (1).

256628677 is an equidigital number, since it uses as much as digits as its factorization.

256628677 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1693440, while the sum is 49.

The square root of 256628677 is about 16019.6341094296. The cubic root of 256628677 is about 635.4797680383.

The spelling of 256628677 in words is "two hundred fifty-six million, six hundred twenty-eight thousand, six hundred seventy-seven".