79809137 has 2 divisors, whose sum is σ = 79809138. Its totient is φ = 79809136.

The previous prime is 79809091. The next prime is 79809173. The reversal of 79809137 is 73190897.

Together with next prime (79809173) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 70543201 + 9265936 = 8399^2 + 3044^2 .

It is a cyclic number.

It is not a de Polignac number, because 79809137 - 2¹⁸ = 79546993 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (79809187) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39904568 + 39904569.

It is an arithmetic number, because the mean of its divisors is an integer number (39904569).

Almost surely, 2^79809137 is an apocalyptic number.

It is an amenable number.

79809137 is a deficient number, since it is larger than the sum of its proper divisors (1).

79809137 is an equidigital number, since it uses as much as digits as its factorization.

79809137 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 95256, while the sum is 44.

The square root of 79809137 is about 8933.5959725074. The cubic root of 79809137 is about 430.5439969099.

The spelling of 79809137 in words is "seventy-nine million, eight hundred nine thousand, one hundred thirty-seven".