7921979 has 16 divisors (see below), whose sum is σ = 8890560. Its totient is φ = 7011840.

The previous prime is 7921943. The next prime is 7921981. The reversal of 7921979 is 9791297.

It is a cyclic number.

It is not a de Polignac number, because 7921979 - 2⁸ = 7921723 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7921909) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 47354 + ... + 47520.

It is an arithmetic number, because the mean of its divisors is an integer number (555660).

Almost surely, 2^7921979 is an apocalyptic number.

7921979 is a deficient number, since it is larger than the sum of its proper divisors (968581).

7921979 is a wasteful number, since it uses less digits than its factorization.

7921979 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 310.

The product of its digits is 71442, while the sum is 44.

The square root of 7921979 is about 2814.6010374474. The cubic root of 7921979 is about 199.3476998354.

The spelling of 7921979 in words is "seven million, nine hundred twenty-one thousand, nine hundred seventy-nine".