256400544 has 48 divisors (see below), whose sum is σ = 675168480. Its totient is φ = 85198080.

The previous prime is 256400539. The next prime is 256400549. The reversal of 256400544 is 445004652.

It is an interprime number because it is at equal distance from previous prime (256400539) and next prime (256400549).

It is a tau number, because it is divible by the number of its divisors (48).

It is not an unprimeable number, because it can be changed into a prime (256400549) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 27742 + ... + 35810.

It is an arithmetic number, because the mean of its divisors is an integer number (14066010).

Almost surely, 2^256400544 is an apocalyptic number.

256400544 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

256400544 is an abundant number, since it is smaller than the sum of its proper divisors (418767936).

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

256400544 is a wasteful number, since it uses less digits than its factorization.

256400544 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8413 (or 8405 counting only the distinct ones).

The product of its (nonzero) digits is 19200, while the sum is 30.

The square root of 256400544 is about 16012.5121077238. The cubic root of 256400544 is about 635.2914065405.

The spelling of 256400544 in words is "two hundred fifty-six million, four hundred thousand, five hundred forty-four".