257506440 has 64 divisors (see below), whose sum is σ = 774835200. Its totient is φ = 68462592.

The previous prime is 257506427. The next prime is 257506451. The reversal of 257506440 is 44605752.

257506440 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 39321 + ... + 45399.

It is an arithmetic number, because the mean of its divisors is an integer number (12106800).

Almost surely, 2^257506440 is an apocalyptic number.

257506440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 257506440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (387417600).

257506440 is an abundant number, since it is smaller than the sum of its proper divisors (517328760).

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

257506440 is a wasteful number, since it uses less digits than its factorization.

257506440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6446 (or 6442 counting only the distinct ones).

The product of its (nonzero) digits is 33600, while the sum is 33.

The square root of 257506440 is about 16047.0071976054. The cubic root of 257506440 is about 636.2034671974.

The spelling of 257506440 in words is "two hundred fifty-seven million, five hundred six thousand, four hundred forty".