78999657 has 8 divisors (see below), whose sum is σ = 114908640. Its totient is φ = 47878560.

The previous prime is 78999631. The next prime is 78999689. The reversal of 78999657 is 75699987.

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

It is not a de Polignac number, because 78999657 - 2⁶ = 78999593 is a prime.

It is a super-2 number, since 2×78999657² = 12481891612235298, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 78999657.

It is not an unprimeable number, because it can be changed into a prime (78999257) 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 7 ways as a sum of consecutive naturals, for example, 1196932 + ... + 1196997.

It is an arithmetic number, because the mean of its divisors is an integer number (14363580).

Almost surely, 2^78999657 is an apocalyptic number.

It is an amenable number.

78999657 is a deficient number, since it is larger than the sum of its proper divisors (35908983).

78999657 is a wasteful number, since it uses less digits than its factorization.

78999657 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2393943.

The product of its digits is 8573040, while the sum is 60.

The square root of 78999657 is about 8888.1751220371. The cubic root of 78999657 is about 429.0834217067.

The spelling of 78999657 in words is "seventy-eight million, nine hundred ninety-nine thousand, six hundred fifty-seven".