79372009 has 2 divisors, whose sum is σ = 79372010. Its totient is φ = 79372008.

The previous prime is 79371979. The next prime is 79372021. The reversal of 79372009 is 90027397.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 70610409 + 8761600 = 8403^2 + 2960^2 .

It is a cyclic number.

It is not a de Polignac number, because 79372009 - 2⁵ = 79371977 is a prime.

It is equal to p_4634866 and since 79372009 and 4634866 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (79372039) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39686004 + 39686005.

It is an arithmetic number, because the mean of its divisors is an integer number (39686005).

Almost surely, 2^79372009 is an apocalyptic number.

It is an amenable number.

79372009 is a deficient number, since it is larger than the sum of its proper divisors (1).

79372009 is an equidigital number, since it uses as much as digits as its factorization.

79372009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 23814, while the sum is 37.

The square root of 79372009 is about 8909.0969800536. The cubic root of 79372009 is about 429.7565035689.

The spelling of 79372009 in words is "seventy-nine million, three hundred seventy-two thousand, nine".