257628 has 24 divisors (see below), whose sum is σ = 687232. Its totient is φ = 73584.

The previous prime is 257627. The next prime is 257639. The reversal of 257628 is 826752.

It is a Smith number, since the sum of its digits (30) coincides with the sum of the digits of its prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 257595 and 257604.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (257627) 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, 1450 + ... + 1617.

2²⁵⁷⁶²⁸ is an apocalyptic number.

257628 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

257628 is an abundant number, since it is smaller than the sum of its proper divisors (429604).

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

257628 is a wasteful number, since it uses less digits than its factorization.

257628 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3081 (or 3079 counting only the distinct ones).

The product of its digits is 6720, while the sum is 30.

The square root of 257628 is about 507.5706847327. The cubic root of 257628 is about 63.6303561428.

It can be divided in two parts, 2 and 57628, that added together give a triangular number (57630 = T₃₃₉).

The spelling of 257628 in words is "two hundred fifty-seven thousand, six hundred twenty-eight".