79689840 has 80 divisors (see below), whose sum is σ = 255031296. Its totient is φ = 20563200.

The previous prime is 79689839. The next prime is 79689887. The reversal of 79689840 is 4898697.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2085 + ... + 12795.

Almost surely, 2^79689840 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 79689840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (127515648).

79689840 is an abundant number, since it is smaller than the sum of its proper divisors (175341456).

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

79689840 is a wasteful number, since it uses less digits than its factorization.

79689840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10758 (or 10752 counting only the distinct ones).

The product of its (nonzero) digits is 870912, while the sum is 51.

The square root of 79689840 is about 8926.9166009323. The cubic root of 79689840 is about 430.3293672642.

The spelling of 79689840 in words is "seventy-nine million, six hundred eighty-nine thousand, eight hundred forty".