78661668 has 12 divisors (see below), whose sum is σ = 183543920. Its totient is φ = 26220552.

The previous prime is 78661621. The next prime is 78661697. The reversal of 78661668 is 86616687.

It is a tau number, because it is divible by the number of its divisors (12).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3277558 + ... + 3277581.

Almost surely, 2^78661668 is an apocalyptic number.

It is an amenable number.

78661668 is an abundant number, since it is smaller than the sum of its proper divisors (104882252).

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

78661668 is a wasteful number, since it uses less digits than its factorization.

78661668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6555146 (or 6555144 counting only the distinct ones).

The product of its digits is 580608, while the sum is 48.

The square root of 78661668 is about 8869.1413338609. The cubic root of 78661668 is about 428.4706224495.

The spelling of 78661668 in words is "seventy-eight million, six hundred sixty-one thousand, six hundred sixty-eight".