79923813 has 4 divisors (see below), whose sum is σ = 106565088. Its totient is φ = 53282540.

The previous prime is 79923791. The next prime is 79923839. The reversal of 79923813 is 31832997.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 79923813 - 2¹² = 79919717 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (79923853) 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, 13320633 + ... + 13320638.

It is an arithmetic number, because the mean of its divisors is an integer number (26641272).

Almost surely, 2^79923813 is an apocalyptic number.

It is an amenable number.

79923813 is a deficient number, since it is larger than the sum of its proper divisors (26641275).

79923813 is a wasteful number, since it uses less digits than its factorization.

79923813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26641274.

The product of its digits is 81648, while the sum is 42.

The square root of 79923813 is about 8940.0119127437. The cubic root of 79923813 is about 430.7501112990.

The spelling of 79923813 in words is "seventy-nine million, nine hundred twenty-three thousand, eight hundred thirteen".