77442979 has 2 divisors, whose sum is σ = 77442980. Its totient is φ = 77442978.

The previous prime is 77442943. The next prime is 77442997. The reversal of 77442979 is 97924477.

Together with next prime (77442997) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 77442979 - 2⁷ = 77442851 is a prime.

It is not a weakly prime, because it can be changed into another prime (77446979) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38721489 + 38721490.

It is an arithmetic number, because the mean of its divisors is an integer number (38721490).

Almost surely, 2^77442979 is an apocalyptic number.

77442979 is a deficient number, since it is larger than the sum of its proper divisors (1).

77442979 is an equidigital number, since it uses as much as digits as its factorization.

77442979 is an evil number, because the sum of its binary digits is even.

The product of its digits is 889056, while the sum is 49.

The square root of 77442979 is about 8800.1692597359. The cubic root of 77442979 is about 426.2463602513.

The spelling of 77442979 in words is "seventy-seven million, four hundred forty-two thousand, nine hundred seventy-nine".