81332874979 has 2 divisors, whose sum is σ = 81332874980. Its totient is φ = 81332874978.

The previous prime is 81332874943. The next prime is 81332875037. The reversal of 81332874979 is 97947823318.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 81332874979 - 2⁷ = 81332874851 is a prime.

It is not a weakly prime, because it can be changed into another prime (81332875979) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40666437489 + 40666437490.

It is an arithmetic number, because the mean of its divisors is an integer number (40666437490).

Almost surely, 2^81332874979 is an apocalyptic number.

81332874979 is a deficient number, since it is larger than the sum of its proper divisors (1).

81332874979 is an equidigital number, since it uses as much as digits as its factorization.

81332874979 is an evil number, because the sum of its binary digits is even.

The product of its digits is 18289152, while the sum is 61.

The spelling of 81332874979 in words is "eighty-one billion, three hundred thirty-two million, eight hundred seventy-four thousand, nine hundred seventy-nine".