79543021 has 4 divisors (see below), whose sum is σ = 80169472. Its totient is φ = 78916572.

The previous prime is 79543019. The next prime is 79543049. The reversal of 79543021 is 12034597.

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 79543021 - 2¹ = 79543019 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (79543621) 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, 313035 + ... + 313288.

It is an arithmetic number, because the mean of its divisors is an integer number (20042368).

Almost surely, 2^79543021 is an apocalyptic number.

It is an amenable number.

79543021 is a deficient number, since it is larger than the sum of its proper divisors (626451).

79543021 is a wasteful number, since it uses less digits than its factorization.

79543021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 626450.

The product of its (nonzero) digits is 7560, while the sum is 31.

The square root of 79543021 is about 8918.6894216583. The cubic root of 79543021 is about 430.0649279999.

The spelling of 79543021 in words is "seventy-nine million, five hundred forty-three thousand, twenty-one".