78394928 has 10 divisors (see below), whose sum is σ = 151890204. Its totient is φ = 39197456.

The previous prime is 78394913. The next prime is 78394949. The reversal of 78394928 is 82949387.

It is a happy number.

It is a super-2 number, since 2×78394928² = 12291529472250368, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2449826 + ... + 2449857.

Almost surely, 2^78394928 is an apocalyptic number.

It is an amenable number.

78394928 is a deficient number, since it is larger than the sum of its proper divisors (73495276).

78394928 is a wasteful number, since it uses less digits than its factorization.

78394928 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4899691 (or 4899685 counting only the distinct ones).

The product of its digits is 870912, while the sum is 50.

The square root of 78394928 is about 8854.0910318338. The cubic root of 78394928 is about 427.9857624751.

The spelling of 78394928 in words is "seventy-eight million, three hundred ninety-four thousand, nine hundred twenty-eight".