78955209 has 8 divisors (see below), whose sum is σ = 116970720. Its totient is φ = 52636788.

The previous prime is 78955183. The next prime is 78955231. The reversal of 78955209 is 90255987.

It is a happy number.

It is not a de Polignac number, because 78955209 - 2²⁵ = 45400777 is a prime.

It is not an unprimeable number, because it can be changed into a prime (78955909) 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, 1462107 + ... + 1462160.

It is an arithmetic number, because the mean of its divisors is an integer number (14621340).

Almost surely, 2^78955209 is an apocalyptic number.

It is an amenable number.

78955209 is a deficient number, since it is larger than the sum of its proper divisors (38015511).

78955209 is a wasteful number, since it uses less digits than its factorization.

78955209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2924276 (or 2924270 counting only the distinct ones).

The product of its (nonzero) digits is 226800, while the sum is 45.

The square root of 78955209 is about 8885.6743694556. The cubic root of 78955209 is about 429.0029341087.

The spelling of 78955209 in words is "seventy-eight million, nine hundred fifty-five thousand, two hundred nine".