79997220 has 240 divisors, whose sum is σ = 278087040. Its totient is φ = 19160064.

The previous prime is 79997207. The next prime is 79997221. The reversal of 79997220 is 2279997.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (79997221) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 707884 + ... + 707996.

It is an arithmetic number, because the mean of its divisors is an integer number (1158696).

Almost surely, 2^79997220 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 79997220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (139043520).

79997220 is an abundant number, since it is smaller than the sum of its proper divisors (198089820).

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

79997220 is a wasteful number, since it uses less digits than its factorization.

79997220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 176 (or 165 counting only the distinct ones).

The product of its (nonzero) digits is 142884, while the sum is 45.

The square root of 79997220 is about 8944.1165019246. The cubic root of 79997220 is about 430.8819468415.

The spelling of 79997220 in words is "seventy-nine million, nine hundred ninety-seven thousand, two hundred twenty".