78979999 has 8 divisors (see below), whose sum is σ = 94187520. Its totient is φ = 64753656.

The previous prime is 78979997. The next prime is 78980009. The reversal of 78979999 is 99997987.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 78979999 - 2¹ = 78979997 is a prime.

78979999 is a modest number, since divided by 9999 gives 7897 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78979997) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 245119 + ... + 245440.

It is an arithmetic number, because the mean of its divisors is an integer number (11773440).

Almost surely, 2^78979999 is an apocalyptic number.

78979999 is a deficient number, since it is larger than the sum of its proper divisors (15207521).

78979999 is a wasteful number, since it uses less digits than its factorization.

78979999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 490589.

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

The square root of 78979999 is about 8887.0692019360. The cubic root of 78979999 is about 429.0478282119.

The spelling of 78979999 in words is "seventy-eight million, nine hundred seventy-nine thousand, nine hundred ninety-nine".