6689718021 has 16 divisors (see below), whose sum is σ = 10197615744. Its totient is φ = 3821286144.

The previous prime is 6689718011. The next prime is 6689718071. The reversal of 6689718021 is 1208179866.

It is not a de Polignac number, because 6689718021 - 2⁵ = 6689717989 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6689718011) 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, 961 + ... + 115673.

It is an arithmetic number, because the mean of its divisors is an integer number (637350984).

Almost surely, 2^6689718021 is an apocalyptic number.

It is an amenable number.

6689718021 is a deficient number, since it is larger than the sum of its proper divisors (3507897723).

6689718021 is a wasteful number, since it uses less digits than its factorization.

6689718021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 117500.

The product of its (nonzero) digits is 290304, while the sum is 48.

The square root of 6689718021 is about 81790.6964208033. The cubic root of 6689718021 is about 1884.2387778802.

The spelling of 6689718021 in words is "six billion, six hundred eighty-nine million, seven hundred eighteen thousand, twenty-one".