78515991604 has 12 divisors (see below), whose sum is σ = 137514612928. Its totient is φ = 39226102200.

The previous prime is 78515991553. The next prime is 78515991637. The reversal of 78515991604 is 40619951587.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7967862 + ... + 7977709.

Almost surely, 2^78515991604 is an apocalyptic number.

It is an amenable number.

78515991604 is a deficient number, since it is larger than the sum of its proper divisors (58998621324).

78515991604 is a wasteful number, since it uses less digits than its factorization.

78515991604 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15946806 (or 15946804 counting only the distinct ones).

The product of its (nonzero) digits is 2721600, while the sum is 55.

The spelling of 78515991604 in words is "seventy-eight billion, five hundred fifteen million, nine hundred ninety-one thousand, six hundred four".