6679400721 has 16 divisors (see below), whose sum is σ = 10620662784. Its totient is φ = 3650852304.

The previous prime is 6679400713. The next prime is 6679400801. The reversal of 6679400721 is 1270049766.

6679400721 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 6679400721 - 2³ = 6679400713 is a prime.

It is a super-2 number, since 2×6679400721² = 89228787983390639682, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (6679400711) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6914011 + ... + 6914976.

It is an arithmetic number, because the mean of its divisors is an integer number (663791424).

Almost surely, 2^6679400721 is an apocalyptic number.

It is an amenable number.

6679400721 is a deficient number, since it is larger than the sum of its proper divisors (3941262063).

6679400721 is a wasteful number, since it uses less digits than its factorization.

6679400721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13829020.

The product of its (nonzero) digits is 127008, while the sum is 42.

The square root of 6679400721 is about 81727.6007294965. The cubic root of 6679400721 is about 1883.2696159890.

The spelling of 6679400721 in words is "six billion, six hundred seventy-nine million, four hundred thousand, seven hundred twenty-one".