6979721 has 4 divisors (see below), whose sum is σ = 7976832. Its totient is φ = 5982612.

The previous prime is 6979703. The next prime is 6979727. The reversal of 6979721 is 1279796.

It is a happy number.

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 6979721 - 2¹⁴ = 6963337 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6979727) 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, 498545 + ... + 498558.

It is an arithmetic number, because the mean of its divisors is an integer number (1994208).

Almost surely, 2^6979721 is an apocalyptic number.

It is an amenable number.

6979721 is a deficient number, since it is larger than the sum of its proper divisors (997111).

6979721 is an equidigital number, since it uses as much as digits as its factorization.

6979721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 997110.

The product of its digits is 47628, while the sum is 41.

The square root of 6979721 is about 2641.9161606682. The cubic root of 6979721 is about 191.1082142186.

The spelling of 6979721 in words is "six million, nine hundred seventy-nine thousand, seven hundred twenty-one".