6637664397 has 16 divisors (see below), whose sum is σ = 10892577920. Its totient is φ = 3501185472.

The previous prime is 6637664389. The next prime is 6637664443. The reversal of 6637664397 is 7934667366.

6637664397 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 6637664397 - 2³ = 6637664389 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6637664597) 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, 12156622 + ... + 12157167.

It is an arithmetic number, because the mean of its divisors is an integer number (680786120).

Almost surely, 2^6637664397 is an apocalyptic number.

It is an amenable number.

6637664397 is a deficient number, since it is larger than the sum of its proper divisors (4254913523).

6637664397 is a wasteful number, since it uses less digits than its factorization.

6637664397 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24313812.

The product of its digits is 20575296, while the sum is 57.

The square root of 6637664397 is about 81471.8626091241. The cubic root of 6637664397 is about 1879.3388724256.

The spelling of 6637664397 in words is "six billion, six hundred thirty-seven million, six hundred sixty-four thousand, three hundred ninety-seven".