79442009 has 2 divisors, whose sum is σ = 79442010. Its totient is φ = 79442008.

The previous prime is 79441993. The next prime is 79442017. The reversal of 79442009 is 90024497.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 45859984 + 33582025 = 6772^2 + 5795^2 .

It is a cyclic number.

It is not a de Polignac number, because 79442009 - 2⁴ = 79441993 is a prime.

It is a super-2 number, since 2×79442009² = 12622065587912162, which contains 22 as substring.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 79442009.

It is not a weakly prime, because it can be changed into another prime (79442029) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39721004 + 39721005.

It is an arithmetic number, because the mean of its divisors is an integer number (39721005).

Almost surely, 2^79442009 is an apocalyptic number.

It is an amenable number.

79442009 is a deficient number, since it is larger than the sum of its proper divisors (1).

79442009 is an equidigital number, since it uses as much as digits as its factorization.

79442009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 18144, while the sum is 35.

The square root of 79442009 is about 8913.0246830131. The cubic root of 79442009 is about 429.8828038283.

The spelling of 79442009 in words is "seventy-nine million, four hundred forty-two thousand, nine".