813280257 has 40 divisors (see below), whose sum is σ = 1258709760. Its totient is φ = 522767520.

The previous prime is 813280229. The next prime is 813280277. The reversal of 813280257 is 752082318.

813280257 is a `hidden beast` number, since 81 + 328 + 0 + 257 = 666.

It is not a de Polignac number, because 813280257 - 2⁸ = 813280001 is a prime.

It is a super-2 number, since 2×813280257² = 1322849552851972098, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (813280277) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 1051723 + ... + 1052495.

It is an arithmetic number, because the mean of its divisors is an integer number (31467744).

Almost surely, 2^813280257 is an apocalyptic number.

It is an amenable number.

813280257 is a deficient number, since it is larger than the sum of its proper divisors (445429503).

813280257 is a wasteful number, since it uses less digits than its factorization.

813280257 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1235 (or 1226 counting only the distinct ones).

The product of its (nonzero) digits is 26880, while the sum is 36.

The square root of 813280257 is about 28518.0689563652. The cubic root of 813280257 is about 933.4263929177.

The spelling of 813280257 in words is "eight hundred thirteen million, two hundred eighty thousand, two hundred fifty-seven".