77869931 has 2 divisors, whose sum is σ = 77869932. Its totient is φ = 77869930.

The previous prime is 77869921. The next prime is 77869949. The reversal of 77869931 is 13996877.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-77869931 is a prime.

It is a super-2 number, since 2×77869931² = 12127452307889522, which contains 22 as substring.

It is a Sophie Germain prime.

It is a self number, because there is not a number n which added to its sum of digits gives 77869931.

It is not a weakly prime, because it can be changed into another prime (77869921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38934965 + 38934966.

It is an arithmetic number, because the mean of its divisors is an integer number (38934966).

Almost surely, 2^77869931 is an apocalyptic number.

77869931 is a deficient number, since it is larger than the sum of its proper divisors (1).

77869931 is an equidigital number, since it uses as much as digits as its factorization.

77869931 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 571536, while the sum is 50.

The square root of 77869931 is about 8824.3940868481. The cubic root of 77869931 is about 427.0282401197.

The spelling of 77869931 in words is "seventy-seven million, eight hundred sixty-nine thousand, nine hundred thirty-one".