257240440 has 64 divisors (see below), whose sum is σ = 604843200. Its totient is φ = 98337792.

The previous prime is 257240407. The next prime is 257240453. The reversal of 257240440 is 44042752.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 257240399 and 257240408.

It is a congruent number.

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, 118404 + ... + 120556.

It is an arithmetic number, because the mean of its divisors is an integer number (9450675).

Almost surely, 2^257240440 is an apocalyptic number.

257240440 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 257240440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (302421600).

257240440 is an abundant number, since it is smaller than the sum of its proper divisors (347602760).

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

257240440 is a wasteful number, since it uses less digits than its factorization.

257240440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2296 (or 2292 counting only the distinct ones).

The product of its (nonzero) digits is 8960, while the sum is 28.

The square root of 257240440 is about 16038.7169062865. The cubic root of 257240440 is about 635.9843290840.

The spelling of 257240440 in words is "two hundred fifty-seven million, two hundred forty thousand, four hundred forty".