79899999 has 16 divisors (see below), whose sum is σ = 111456000. Its totient is φ = 50817536.

The previous prime is 79899973. The next prime is 79900001. The reversal of 79899999 is 99999897.

It is a cyclic number.

It is not a de Polignac number, because 79899999 - 2⁹ = 79899487 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (69).

79899999 is a modest number, since divided by 9999 gives 7989 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (79899929) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 29692 + ... + 32270.

It is an arithmetic number, because the mean of its divisors is an integer number (6966000).

Almost surely, 2^79899999 is an apocalyptic number.

79899999 is a deficient number, since it is larger than the sum of its proper divisors (31556001).

79899999 is a wasteful number, since it uses less digits than its factorization.

79899999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3054.

The product of its digits is 29760696, while the sum is 69.

The square root of 79899999 is about 8938.6799360979. The cubic root of 79899999 is about 430.7073251266.

The spelling of 79899999 in words is "seventy-nine million, eight hundred ninety-nine thousand, nine hundred ninety-nine".