77789939 has 2 divisors, whose sum is σ = 77789940. Its totient is φ = 77789938.

The previous prime is 77789923. The next prime is 77789951. The reversal of 77789939 is 93998777.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 77789939 - 2⁴ = 77789923 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (77789039) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38894969 + 38894970.

It is an arithmetic number, because the mean of its divisors is an integer number (38894970).

Almost surely, 2^77789939 is an apocalyptic number.

77789939 is a deficient number, since it is larger than the sum of its proper divisors (1).

77789939 is an equidigital number, since it uses as much as digits as its factorization.

77789939 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6001128, while the sum is 59.

The square root of 77789939 is about 8819.8604864249. The cubic root of 77789939 is about 426.8819682285.

The spelling of 77789939 in words is "seventy-seven million, seven hundred eighty-nine thousand, nine hundred thirty-nine".