79191780 has 72 divisors (see below), whose sum is σ = 235599168. Its totient is φ = 19871232.

The previous prime is 79191769. The next prime is 79191781. The reversal of 79191780 is 8719197.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (79191781) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 15057 + ... + 19623.

Almost surely, 2^79191780 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 79191780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (117799584).

79191780 is an abundant number, since it is smaller than the sum of its proper divisors (156407388).

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

79191780 is a wasteful number, since it uses less digits than its factorization.

79191780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4613 (or 4594 counting only the distinct ones).

The product of its (nonzero) digits is 31752, while the sum is 42.

The square root of 79191780 is about 8898.9763456254. The cubic root of 79191780 is about 429.4309761990.

The spelling of 79191780 in words is "seventy-nine million, one hundred ninety-one thousand, seven hundred eighty".