77127979 has 2 divisors, whose sum is σ = 77127980. Its totient is φ = 77127978.

The previous prime is 77127961. The next prime is 77127983. The reversal of 77127979 is 97972177.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 77127979 - 2⁹ = 77127467 is a prime.

It is not a weakly prime, because it can be changed into another prime (77127959) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38563989 + 38563990.

It is an arithmetic number, because the mean of its divisors is an integer number (38563990).

Almost surely, 2^77127979 is an apocalyptic number.

77127979 is a deficient number, since it is larger than the sum of its proper divisors (1).

77127979 is an equidigital number, since it uses as much as digits as its factorization.

77127979 is an evil number, because the sum of its binary digits is even.

The product of its digits is 388962, while the sum is 49.

The square root of 77127979 is about 8782.2536401541. The cubic root of 77127979 is about 425.6676546342.

The spelling of 77127979 in words is "seventy-seven million, one hundred twenty-seven thousand, nine hundred seventy-nine".