79219840 has 64 divisors (see below), whose sum is σ = 216452160. Its totient is φ = 27159552.

The previous prime is 79219837. The next prime is 79219841. The reversal of 79219840 is 4891297.

It is a tau number, because it is divible by the number of its divisors (64).

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a junction number, because it is equal to n+sod(n) for n = 79219793 and 79219802.

It is not an unprimeable number, because it can be changed into a prime (79219841) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4362 + ... + 13321.

It is an arithmetic number, because the mean of its divisors is an integer number (3382065).

Almost surely, 2^79219840 is an apocalyptic number.

79219840 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

79219840 is an abundant number, since it is smaller than the sum of its proper divisors (137232320).

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

79219840 is a wasteful number, since it uses less digits than its factorization.

79219840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17709 (or 17697 counting only the distinct ones).

The product of its (nonzero) digits is 36288, while the sum is 40.

The square root of 79219840 is about 8900.5527918214. The cubic root of 79219840 is about 429.4816902600.

The spelling of 79219840 in words is "seventy-nine million, two hundred nineteen thousand, eight hundred forty".