78866646 has 16 divisors (see below), whose sum is σ = 157828608. Its totient is φ = 26273000.

The previous prime is 78866639. The next prime is 78866677. The reversal of 78866646 is 64666887.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11311 + ... + 16901.

It is an arithmetic number, because the mean of its divisors is an integer number (9864288).

Almost surely, 2^78866646 is an apocalyptic number.

78866646 is an abundant number, since it is smaller than the sum of its proper divisors (78961962).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

78866646 is a wasteful number, since it uses less digits than its factorization.

78866646 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7947.

The product of its digits is 2322432, while the sum is 51.

The square root of 78866646 is about 8880.6895002584. The cubic root of 78866646 is about 428.8424718167.

The spelling of 78866646 in words is "seventy-eight million, eight hundred sixty-six thousand, six hundred forty-six".