7957664991 has 16 divisors (see below), whose sum is σ = 11855001600. Its totient is φ = 5275469304.

The previous prime is 7957664977. The next prime is 7957665013. The reversal of 7957664991 is 1994667597.

7957664991 is a `hidden beast` number, since 79 + 5 + 76 + 6 + 499 + 1 = 666.

It is not a de Polignac number, because 7957664991 - 2⁶ = 7957664927 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7957664941) 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, 818431 + ... + 828096.

It is an arithmetic number, because the mean of its divisors is an integer number (740937600).

Almost surely, 2^7957664991 is an apocalyptic number.

7957664991 is a deficient number, since it is larger than the sum of its proper divisors (3897336609).

7957664991 is a wasteful number, since it uses less digits than its factorization.

7957664991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1646715 (or 1646709 counting only the distinct ones).

The product of its digits is 25719120, while the sum is 63.

The square root of 7957664991 is about 89205.7452802228. The cubic root of 7957664991 is about 1996.4658411224.

The spelling of 7957664991 in words is "seven billion, nine hundred fifty-seven million, six hundred sixty-four thousand, nine hundred ninety-one".