101920 has 72 divisors (see below), whose sum is σ = 301644. Its totient is φ = 32256.

The previous prime is 101917. The next prime is 101921. The reversal of 101920 is 29101.

It can be written as a sum of positive squares in 2 ways, for example, as 94864 + 7056 = 308^2 + 84^2 .

It is a Harshad number since it is a multiple of its sum of digits (13).

It is a self number, because there is not a number n which added to its sum of digits gives 101920.

It is not an unprimeable number, because it can be changed into a prime (101921) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7834 + ... + 7846.

2¹⁰¹⁹²⁰ is an apocalyptic number.

101920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

101920 is the 160-th decagonal number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 101920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (150822).

101920 is an abundant number, since it is smaller than the sum of its proper divisors (199724).

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

101920 is a wasteful number, since it uses less digits than its factorization.

101920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42 (or 27 counting only the distinct ones).

The product of its (nonzero) digits is 18, while the sum is 13.

The square root of 101920 is about 319.2491190278. The cubic root of 101920 is about 46.7110688501.

The spelling of 101920 in words is "one hundred one thousand, nine hundred twenty".