256806992 has 60 divisors (see below), whose sum is σ = 546582204. Its totient is φ = 116812800.

The previous prime is 256806961. The next prime is 256806997. The reversal of 256806992 is 299608652.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 114147856 + 142659136 = 10684^2 + 11944^2 .

It is a super-2 number, since 2×256806992² = 131899662280176128, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256806997) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 196742 + ... + 198042.

Almost surely, 2^256806992 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 256806992, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (273291102).

256806992 is an abundant number, since it is smaller than the sum of its proper divisors (289775212).

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

256806992 is a wasteful number, since it uses less digits than its factorization.

256806992 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1408 (or 1389 counting only the distinct ones).

The product of its (nonzero) digits is 466560, while the sum is 47.

The square root of 256806992 is about 16025.1986571150. The cubic root of 256806992 is about 635.6269188309.

The spelling of 256806992 in words is "two hundred fifty-six million, eight hundred six thousand, nine hundred ninety-two".