78536818509 has 32 divisors (see below), whose sum is σ = 110378557440. Its totient is φ = 49573886208.

The previous prime is 78536818487. The next prime is 78536818511. The reversal of 78536818509 is 90581863587.

It is not a de Polignac number, because 78536818509 - 2²⁰ = 78535769933 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78536818309) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 6410812 + ... + 6423050.

It is an arithmetic number, because the mean of its divisors is an integer number (3449329920).

Almost surely, 2^78536818509 is an apocalyptic number.

It is an amenable number.

78536818509 is a deficient number, since it is larger than the sum of its proper divisors (31841738931).

78536818509 is a wasteful number, since it uses less digits than its factorization.

78536818509 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13201.

The product of its (nonzero) digits is 14515200, while the sum is 60.

The spelling of 78536818509 in words is "seventy-eight billion, five hundred thirty-six million, eight hundred eighteen thousand, five hundred nine".