79680640647 has 32 divisors (see below), whose sum is σ = 108642643200. Its totient is φ = 51930382592.

The previous prime is 79680640643. The next prime is 79680640679. The reversal of 79680640647 is 74604608697.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 79680640647 - 2² = 79680640643 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (79680640643) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 29196379 + ... + 29199107.

It is an arithmetic number, because the mean of its divisors is an integer number (3395082600).

Almost surely, 2^79680640647 is an apocalyptic number.

79680640647 is a deficient number, since it is larger than the sum of its proper divisors (28962002553).

79680640647 is a wasteful number, since it uses less digits than its factorization.

79680640647 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3647.

The product of its (nonzero) digits is 12192768, while the sum is 57.

The spelling of 79680640647 in words is "seventy-nine billion, six hundred eighty million, six hundred forty thousand, six hundred forty-seven".