79931539991 has 2 divisors, whose sum is σ = 79931539992. Its totient is φ = 79931539990.

The previous prime is 79931539969. The next prime is 79931540023. The reversal of 79931539991 is 19993513997.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-79931539991 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (79931539931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39965769995 + 39965769996.

It is an arithmetic number, because the mean of its divisors is an integer number (39965769996).

Almost surely, 2^79931539991 is an apocalyptic number.

79931539991 is a deficient number, since it is larger than the sum of its proper divisors (1).

79931539991 is an equidigital number, since it uses as much as digits as its factorization.

79931539991 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 18600435, while the sum is 65.

The spelling of 79931539991 in words is "seventy-nine billion, nine hundred thirty-one million, five hundred thirty-nine thousand, nine hundred ninety-one".