78779728 has 20 divisors (see below), whose sum is σ = 152920768. Its totient is φ = 39316320.

The previous prime is 78779671. The next prime is 78779777. The reversal of 78779728 is 82797787.

It is a happy number.

It is a congruent number.

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, 4825 + ... + 13447.

Almost surely, 2^78779728 is an apocalyptic number.

It is an amenable number.

78779728 is a deficient number, since it is larger than the sum of its proper divisors (74141040).

78779728 is a wasteful number, since it uses less digits than its factorization.

78779728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9202 (or 9196 counting only the distinct ones).

The product of its digits is 2765952, while the sum is 55.

The square root of 78779728 is about 8875.7944996490. The cubic root of 78779728 is about 428.6848731639.

It can be divided in two parts, 78779 and 728, that added together give a cube (79507 = 43³).

The spelling of 78779728 in words is "seventy-eight million, seven hundred seventy-nine thousand, seven hundred twenty-eight".