78664028 has 24 divisors (see below), whose sum is σ = 148283520. Its totient is φ = 36393840.

The previous prime is 78664021. The next prime is 78664039. The reversal of 78664028 is 82046687.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78664021) by changing a digit.

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 in 7 ways as a sum of consecutive naturals, for example, 8768 + ... + 15303.

It is an arithmetic number, because the mean of its divisors is an integer number (6178480).

Almost surely, 2^78664028 is an apocalyptic number.

It is an amenable number.

78664028 is a deficient number, since it is larger than the sum of its proper divisors (69619492).

78664028 is a wasteful number, since it uses less digits than its factorization.

78664028 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24137 (or 24135 counting only the distinct ones).

The product of its (nonzero) digits is 129024, while the sum is 41.

The square root of 78664028 is about 8869.2743784371. The cubic root of 78664028 is about 428.4749073852.

The spelling of 78664028 in words is "seventy-eight million, six hundred sixty-four thousand, twenty-eight".