78639823206 has 24 divisors (see below), whose sum is σ = 194727181584. Its totient is φ = 22468520880.

The previous prime is 78639823183. The next prime is 78639823217. The reversal of 78639823206 is 60232893687.

It is a happy number.

It is a super-2 number, since 2×78639823206² (a number of 23 digits) contains 22 as substring.

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 11 ways as a sum of consecutive naturals, for example, 312062665 + ... + 312062916.

It is an arithmetic number, because the mean of its divisors is an integer number (8113632566).

Almost surely, 2^78639823206 is an apocalyptic number.

78639823206 is an abundant number, since it is smaller than the sum of its proper divisors (116087358378).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

78639823206 is a wasteful number, since it uses less digits than its factorization.

78639823206 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 624125596 (or 624125593 counting only the distinct ones).

The product of its (nonzero) digits is 5225472, while the sum is 54.

The spelling of 78639823206 in words is "seventy-eight billion, six hundred thirty-nine million, eight hundred twenty-three thousand, two hundred six".