78999969 has 16 divisors (see below), whose sum is σ = 112416768. Its totient is φ = 49174272.

The previous prime is 78999961. The next prime is 78999979. The reversal of 78999969 is 96999987.

It is not a de Polignac number, because 78999969 - 2³ = 78999961 is a prime.

It is a super-2 number, since 2×78999969² = 12481990204001922, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (78999961) 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 15 ways as a sum of consecutive naturals, for example, 379 + ... + 12575.

It is an arithmetic number, because the mean of its divisors is an integer number (7026048).

Almost surely, 2^78999969 is an apocalyptic number.

It is an amenable number.

78999969 is a deficient number, since it is larger than the sum of its proper divisors (33416799).

78999969 is a wasteful number, since it uses less digits than its factorization.

78999969 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12344.

The product of its digits is 19840464, while the sum is 66.

The square root of 78999969 is about 8888.1926734292. The cubic root of 78999969 is about 429.0839865777.

The spelling of 78999969 in words is "seventy-eight million, nine hundred ninety-nine thousand, nine hundred sixty-nine".