78409691504 has 20 divisors (see below), whose sum is σ = 151923928776. Its totient is φ = 39203516352.

The previous prime is 78409691491. The next prime is 78409691509. The reversal of 78409691504 is 40519690487.

It is a super-2 number, since 2×78409691504² (a number of 23 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (53) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78409691509) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 549407 + ... + 677249.

Almost surely, 2^78409691504 is an apocalyptic number.

It is an amenable number.

78409691504 is a deficient number, since it is larger than the sum of its proper divisors (73514237272).

78409691504 is a wasteful number, since it uses less digits than its factorization.

78409691504 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 166184 (or 166178 counting only the distinct ones).

The product of its (nonzero) digits is 2177280, while the sum is 53.

The spelling of 78409691504 in words is "seventy-eight billion, four hundred nine million, six hundred ninety-one thousand, five hundred four".