79905491 has 4 divisors (see below), whose sum is σ = 84605832. Its totient is φ = 75205152.

The previous prime is 79905461. The next prime is 79905517. The reversal of 79905491 is 19450997.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-79905491 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (79905451) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2350145 + ... + 2350178.

It is an arithmetic number, because the mean of its divisors is an integer number (21151458).

Almost surely, 2^79905491 is an apocalyptic number.

79905491 is a deficient number, since it is larger than the sum of its proper divisors (4700341).

79905491 is a wasteful number, since it uses less digits than its factorization.

79905491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4700340.

The product of its (nonzero) digits is 102060, while the sum is 44.

The square root of 79905491 is about 8938.9871350170. The cubic root of 79905491 is about 430.7171932554.

The spelling of 79905491 in words is "seventy-nine million, nine hundred five thousand, four hundred ninety-one".