7979861691 has 12 divisors (see below), whose sum is σ = 11953373432. Its totient is φ = 5319907632.

The previous prime is 7979861657. The next prime is 7979861713. The reversal of 7979861691 is 1961689797.

7979861691 is a `hidden beast` number, since 7 + 9 + 7 + 9 + 8 + 616 + 9 + 1 = 666.

It is not a de Polignac number, because 7979861691 - 2⁷ = 7979861563 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7979861641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 16419226 + ... + 16419711.

Almost surely, 2^7979861691 is an apocalyptic number.

7979861691 is a deficient number, since it is larger than the sum of its proper divisors (3973511741).

7979861691 is an equidigital number, since it uses as much as digits as its factorization.

7979861691 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32838952 (or 32838940 counting only the distinct ones).

The product of its digits is 10287648, while the sum is 63.

The square root of 7979861691 is about 89330.0715940606. The cubic root of 7979861691 is about 1998.3203974458.

The spelling of 7979861691 in words is "seven billion, nine hundred seventy-nine million, eight hundred sixty-one thousand, six hundred ninety-one".