79023986521 has 4 divisors (see below), whose sum is σ = 79039197412. Its totient is φ = 79008775632.

The previous prime is 79023986507. The next prime is 79023986527. The reversal of 79023986521 is 12568932097.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12568932097 = 83233 ⋅151009.

It can be written as a sum of positive squares in 2 ways, for example, as 57919160896 + 21104825625 = 240664^2 + 145275^2 .

It is a cyclic number.

It is not a de Polignac number, because 79023986521 - 2²¹ = 79021889369 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (79023986527) 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, 7597650 + ... + 7608043.

It is an arithmetic number, because the mean of its divisors is an integer number (19759799353).

Almost surely, 2^79023986521 is an apocalyptic number.

It is an amenable number.

79023986521 is a deficient number, since it is larger than the sum of its proper divisors (15210891).

79023986521 is a wasteful number, since it uses less digits than its factorization.

79023986521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15210890.

The product of its (nonzero) digits is 1632960, while the sum is 52.

The spelling of 79023986521 in words is "seventy-nine billion, twenty-three million, nine hundred eighty-six thousand, five hundred twenty-one".