977639657 has 2 divisors, whose sum is σ = 977639658. Its totient is φ = 977639656.

The previous prime is 977639647. The next prime is 977639693. The reversal of 977639657 is 756936779.

977639657 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 974625961 + 3013696 = 31219^2 + 1736^2 .

It is an emirp because it is prime and its reverse (756936779) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 977639657 - 2⁸ = 977639401 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 977639596 and 977639605.

It is not a weakly prime, because it can be changed into another prime (977639627) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 488819828 + 488819829.

It is an arithmetic number, because the mean of its divisors is an integer number (488819829).

Almost surely, 2^977639657 is an apocalyptic number.

It is an amenable number.

977639657 is a deficient number, since it is larger than the sum of its proper divisors (1).

977639657 is an equidigital number, since it uses as much as digits as its factorization.

977639657 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15002820, while the sum is 59.

The square root of 977639657 is about 31267.2297621647. The cubic root of 977639657 is about 992.4902978788.

The spelling of 977639657 in words is "nine hundred seventy-seven million, six hundred thirty-nine thousand, six hundred fifty-seven".