79999999999 has 2 divisors, whose sum is σ = 80000000000. Its totient is φ = 79999999998.

The previous prime is 79999999993. The next prime is 80000000021. The reversal of 79999999999 is 99999999997.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 79999999999 - 2³⁵ = 45640261631 is a prime.

It is a super-9 number, since 9×79999999999⁹ (a number of 100 digits) contains 999999999 as substring.

79999999999 is a modest number, since divided by 999999 gives 79999 as remainder.

It is a plaindrome in base 10.

It is a self number, because there is not a number n which added to its sum of digits gives 79999999999.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (79999999993) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39999999999 + 40000000000.

It is an arithmetic number, because the mean of its divisors is an integer number (40000000000).

Almost surely, 2^79999999999 is an apocalyptic number.

79999999999 is a deficient number, since it is larger than the sum of its proper divisors (1).

79999999999 is an equidigital number, since it uses as much as digits as its factorization.

79999999999 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 24407490807, while the sum is 97.

It can be divided in two parts, 7999999999 and 9, that added together give a palindrome (8000000008).

The spelling of 79999999999 in words is "seventy-nine billion, nine hundred ninety-nine million, nine hundred ninety-nine thousand, nine hundred ninety-nine".