79897999 has 4 divisors (see below), whose sum is σ = 81756136. Its totient is φ = 78039864.

The previous prime is 79897967. The next prime is 79898003. The reversal of 79897999 is 99979897.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 99979897 = 3457 ⋅28921.

It is a cyclic number.

It is not a de Polignac number, because 79897999 - 2⁵ = 79897967 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (79897799) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 929004 + ... + 929089.

It is an arithmetic number, because the mean of its divisors is an integer number (20439034).

Almost surely, 2^79897999 is an apocalyptic number.

79897999 is a deficient number, since it is larger than the sum of its proper divisors (1858137).

79897999 is a wasteful number, since it uses less digits than its factorization.

79897999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1858136.

The product of its digits is 23147208, while the sum is 67.

The square root of 79897999 is about 8938.5680620556. The cubic root of 79897999 is about 430.7037313767.

The spelling of 79897999 in words is "seventy-nine million, eight hundred ninety-seven thousand, nine hundred ninety-nine".