79331557 has 2 divisors, whose sum is σ = 79331558. Its totient is φ = 79331556.

The previous prime is 79331543. The next prime is 79331579. The reversal of 79331557 is 75513397.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 73719396 + 5612161 = 8586^2 + 2369^2 .

It is an emirp because it is prime and its reverse (75513397) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 79331557 - 2⁷ = 79331429 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (79331507) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39665778 + 39665779.

It is an arithmetic number, because the mean of its divisors is an integer number (39665779).

Almost surely, 2^79331557 is an apocalyptic number.

It is an amenable number.

79331557 is a deficient number, since it is larger than the sum of its proper divisors (1).

79331557 is an equidigital number, since it uses as much as digits as its factorization.

79331557 is an evil number, because the sum of its binary digits is even.

The product of its digits is 99225, while the sum is 40.

The square root of 79331557 is about 8906.8264269604. The cubic root of 79331557 is about 429.6834825947.

The spelling of 79331557 in words is "seventy-nine million, three hundred thirty-one thousand, five hundred fifty-seven".