257650820 has 36 divisors (see below), whose sum is σ = 629406540. Its totient is φ = 88337088.

The previous prime is 257650801. The next prime is 257650823. The reversal of 257650820 is 28056752.

257650820 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 183277444 + 74373376 = 13538^2 + 8624^2 .

It is a Harshad number since it is a multiple of its sum of digits (35).

It is not an unprimeable number, because it can be changed into a prime (257650823) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 130475 + ... + 132434.

It is an arithmetic number, because the mean of its divisors is an integer number (17483515).

Almost surely, 2^257650820 is an apocalyptic number.

257650820 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

257650820 is an abundant number, since it is smaller than the sum of its proper divisors (371755720).

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

257650820 is a wasteful number, since it uses less digits than its factorization.

257650820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 262932 (or 262923 counting only the distinct ones).

The product of its (nonzero) digits is 33600, while the sum is 35.

The square root of 257650820 is about 16051.5052253675. The cubic root of 257650820 is about 636.3223482303.

The spelling of 257650820 in words is "two hundred fifty-seven million, six hundred fifty thousand, eight hundred twenty".