257720528 has 20 divisors (see below), whose sum is σ = 537744228. Its totient is φ = 118947840.

The previous prime is 257720513. The next prime is 257720531. The reversal of 257720528 is 825027752.

It can be written as a sum of positive squares in 2 ways, for example, as 40806544 + 216913984 = 6388^2 + 14728^2 .

It is a junction number, because it is equal to n+sod(n) for n = 257720491 and 257720500.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 619313 + ... + 619728.

Almost surely, 2^257720528 is an apocalyptic number.

It is an amenable number.

257720528 is an abundant number, since it is smaller than the sum of its proper divisors (280023700).

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

257720528 is a wasteful number, since it uses less digits than its factorization.

257720528 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1239062 (or 1239056 counting only the distinct ones).

The product of its (nonzero) digits is 78400, while the sum is 38.

The square root of 257720528 is about 16053.6764636640. The cubic root of 257720528 is about 636.3797291960.

The spelling of 257720528 in words is "two hundred fifty-seven million, seven hundred twenty thousand, five hundred twenty-eight".