257720538 has 16 divisors (see below), whose sum is σ = 517404096. Its totient is φ = 85579680.

The previous prime is 257720531. The next prime is 257720539. The reversal of 257720538 is 835027752.

257720538 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a junction number, because it is equal to n+sod(n) for n = 257720496 and 257720505.

It is not an unprimeable number, because it can be changed into a prime (257720531) 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, 80083 + ... + 83238.

It is an arithmetic number, because the mean of its divisors is an integer number (32337756).

Almost surely, 2^257720538 is an apocalyptic number.

257720538 is an abundant number, since it is smaller than the sum of its proper divisors (259683558).

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

257720538 is a wasteful number, since it uses less digits than its factorization.

257720538 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 163589.

The product of its (nonzero) digits is 117600, while the sum is 39.

The square root of 257720538 is about 16053.6767751192. The cubic root of 257720538 is about 636.3797374269.

The spelling of 257720538 in words is "two hundred fifty-seven million, seven hundred twenty thousand, five hundred thirty-eight".