977985257 has 4 divisors (see below), whose sum is σ = 979119360. Its totient is φ = 976851156.

The previous prime is 977985227. The next prime is 977985263. The reversal of 977985257 is 752589779.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 752589779 = 17 ⋅44269987.

It is a cyclic number.

It is not a de Polignac number, because 977985257 - 2²⁸ = 709549801 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 977985196 and 977985205.

It is not an unprimeable number, because it can be changed into a prime (977985227) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 565757 + ... + 567482.

It is an arithmetic number, because the mean of its divisors is an integer number (244779840).

Almost surely, 2^977985257 is an apocalyptic number.

It is an amenable number.

977985257 is a deficient number, since it is larger than the sum of its proper divisors (1134103).

977985257 is a wasteful number, since it uses less digits than its factorization.

977985257 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1134102.

The product of its digits is 11113200, while the sum is 59.

The square root of 977985257 is about 31272.7558267576. The cubic root of 977985257 is about 992.6072340235.

The spelling of 977985257 in words is "nine hundred seventy-seven million, nine hundred eighty-five thousand, two hundred fifty-seven".