79980211210021 has 4 divisors (see below), whose sum is σ = 81930948068844. Its totient is φ = 78029474351200.

The previous prime is 79980211209893. The next prime is 79980211210027. The reversal of 79980211210021 is 12001211208997.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 26640194479396 + 53340016730625 = 5161414^2 + 7303425^2 .

It is a cyclic number.

It is not a de Polignac number, because 79980211210021 - 2⁷ = 79980211209893 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 79980211210021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (79980211210027) 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, 975368429350 + ... + 975368429431.

It is an arithmetic number, because the mean of its divisors is an integer number (20482737017211).

Almost surely, 2^{79980211210021} is an apocalyptic number.

It is an amenable number.

79980211210021 is a deficient number, since it is larger than the sum of its proper divisors (1950736858823).

79980211210021 is a wasteful number, since it uses less digits than its factorization.

79980211210021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1950736858822.

The product of its (nonzero) digits is 36288, while the sum is 43.

The spelling of 79980211210021 in words is "seventy-nine trillion, nine hundred eighty billion, two hundred eleven million, two hundred ten thousand, twenty-one".