1256535880 has 16 divisors (see below), whose sum is σ = 2827205820. Its totient is φ = 502614336.

The previous prime is 1256535877. The next prime is 1256535881. The reversal of 1256535880 is 885356521.

It can be written as a sum of positive squares in 2 ways, for example, as 1256418916 + 116964 = 35446^2 + 342^2 .

It is not an unprimeable number, because it can be changed into a prime (1256535881) 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, 15706659 + ... + 15706738.

Almost surely, 2^1256535880 is an apocalyptic number.

1256535880 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1256535880 is an abundant number, since it is smaller than the sum of its proper divisors (1570669940).

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

1256535880 is a wasteful number, since it uses less digits than its factorization.

1256535880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31413408 (or 31413404 counting only the distinct ones).

The product of its (nonzero) digits is 288000, while the sum is 43.

The square root of 1256535880 is about 35447.6498515769. The cubic root of 1256535880 is about 1079.0915657667.

The spelling of 1256535880 in words is "one billion, two hundred fifty-six million, five hundred thirty-five thousand, eight hundred eighty".