79979400 has 120 divisors (see below), whose sum is σ = 277836570. Its totient is φ = 21323520.

The previous prime is 79979369. The next prime is 79979401. The reversal of 79979400 is 497997.

It can be written as a sum of positive squares in 3 ways, for example, as 56881764 + 23097636 = 7542^2 + 4806^2 .

It is a tau number, because it is divible by the number of its divisors (120).

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

It is not an unprimeable number, because it can be changed into a prime (79979401) by changing a digit.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 13732 + ... + 18668.

Almost surely, 2^79979400 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 79979400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (138918285).

79979400 is an abundant number, since it is smaller than the sum of its proper divisors (197857170).

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

79979400 is a wasteful number, since it uses less digits than its factorization.

79979400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4965 (or 4947 counting only the distinct ones).

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

The square root of 79979400 is about 8943.1202608486. The cubic root of 79979400 is about 430.8499503692.

The spelling of 79979400 in words is "seventy-nine million, nine hundred seventy-nine thousand, four hundred".