161979620 has 48 divisors (see below), whose sum is σ = 373439808. Its totient is φ = 58527360.

The previous prime is 161979577. The next prime is 161979637. The reversal of 161979620 is 26979161.

161979620 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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, 33602 + ... + 38118.

It is an arithmetic number, because the mean of its divisors is an integer number (7779996).

Almost surely, 2^161979620 is an apocalyptic number.

161979620 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 161979620, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (186719904).

161979620 is an abundant number, since it is smaller than the sum of its proper divisors (211460188).

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

161979620 is a wasteful number, since it uses less digits than its factorization.

161979620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4700 (or 4698 counting only the distinct ones).

The product of its (nonzero) digits is 40824, while the sum is 41.

The square root of 161979620 is about 12727.1214341657. The cubic root of 161979620 is about 545.1133170652.

The spelling of 161979620 in words is "one hundred sixty-one million, nine hundred seventy-nine thousand, six hundred twenty".