2256639857 has 4 divisors (see below), whose sum is σ = 2389383396. Its totient is φ = 2123896320.

The previous prime is 2256639829. The next prime is 2256639887. The reversal of 2256639857 is 7589366522.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1065630736 + 1191009121 = 32644^2 + 34511^2 .

It is a cyclic number.

It is not a de Polignac number, because 2256639857 - 2¹⁸ = 2256377713 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2256639799 and 2256639808.

It is not an unprimeable number, because it can be changed into a prime (2256639817) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 66371744 + ... + 66371777.

It is an arithmetic number, because the mean of its divisors is an integer number (597345849).

Almost surely, 2^2256639857 is an apocalyptic number.

It is an amenable number.

2256639857 is a deficient number, since it is larger than the sum of its proper divisors (132743539).

2256639857 is a wasteful number, since it uses less digits than its factorization.

2256639857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 132743538.

The product of its digits is 5443200, while the sum is 53.

The square root of 2256639857 is about 47504.1035806382. The cubic root of 2256639857 is about 1311.6584199710.

The spelling of 2256639857 in words is "two billion, two hundred fifty-six million, six hundred thirty-nine thousand, eight hundred fifty-seven".