256417872 has 20 divisors (see below), whose sum is σ = 662412960. Its totient is φ = 85472608.

The previous prime is 256417867. The next prime is 256417877. The reversal of 256417872 is 278714652.

It is an interprime number because it is at equal distance from previous prime (256417867) and next prime (256417877).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256417877) 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, 2670972 + ... + 2671067.

It is an arithmetic number, because the mean of its divisors is an integer number (33120648).

Almost surely, 2^256417872 is an apocalyptic number.

It is an amenable number.

256417872 is an abundant number, since it is smaller than the sum of its proper divisors (405995088).

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

256417872 is a wasteful number, since it uses less digits than its factorization.

256417872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5342050 (or 5342044 counting only the distinct ones).

The product of its digits is 188160, while the sum is 42.

The square root of 256417872 is about 16013.0531754566. The cubic root of 256417872 is about 635.3057175886.

The spelling of 256417872 in words is "two hundred fifty-six million, four hundred seventeen thousand, eight hundred seventy-two".