78779138180 has 12 divisors (see below), whose sum is σ = 165436190220. Its totient is φ = 31511655264.

The previous prime is 78779138171. The next prime is 78779138209. The reversal of 78779138180 is 8183197787.

It can be written as a sum of positive squares in 2 ways, for example, as 54322557184 + 24456580996 = 233072^2 + 156386^2 .

It is a super-2 number, since 2×78779138180² (a number of 23 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1969478435 + ... + 1969478474.

It is an arithmetic number, because the mean of its divisors is an integer number (13786349185).

Almost surely, 2^78779138180 is an apocalyptic number.

It is an amenable number.

78779138180 is an abundant number, since it is smaller than the sum of its proper divisors (86657052040).

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

78779138180 is a wasteful number, since it uses less digits than its factorization.

78779138180 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3938956918 (or 3938956916 counting only the distinct ones).

The product of its (nonzero) digits is 4741632, while the sum is 59.

The spelling of 78779138180 in words is "seventy-eight billion, seven hundred seventy-nine million, one hundred thirty-eight thousand, one hundred eighty".