256761104656 has 45 divisors (see below), whose sum is σ = 578726968869. Its totient is φ = 110034392832.

The previous prime is 256761104653. The next prime is 256761104671. The reversal of 256761104656 is 656401167652.

The square root of 256761104656 is 506716.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 33584227600 + 223176877056 = 183260^2 + 472416^2 .

It is a Harshad number since it is a multiple of its sum of digits (49).

It is not an unprimeable number, because it can be changed into a prime (256761104653) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 14179000 + ... + 14197096.

Almost surely, 2^256761104656 is an apocalyptic number.

256761104656 is the 506716-th square number.

It is an amenable number.

256761104656 is an abundant number, since it is smaller than the sum of its proper divisors (321965864213).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

256761104656 is an frugal number, since it uses more digits than its factorization.

256761104656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36216 (or 18106 counting only the distinct ones).

The product of its (nonzero) digits is 1814400, while the sum is 49.

Multiplying 256761104656 by its sum of digits (49), we get a square (12581294128144 = 3547012²).

256761104656 divided by its sum of digits (49) gives a square (5240022544 = 72388²).

The spelling of 256761104656 in words is "two hundred fifty-six billion, seven hundred sixty-one million, one hundred four thousand, six hundred fifty-six".