20149920 has 144 divisors (see below), whose sum is σ = 78624000. Its totient is φ = 4603392.

The previous prime is 20149891. The next prime is 20149931. The reversal of 20149920 is 2994102.

It is a tau number, because it is divible by the number of its divisors (144).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9081 + ... + 11079.

It is an arithmetic number, because the mean of its divisors is an integer number (546000).

Almost surely, 2^20149920 is an apocalyptic number.

20149920 is a gapful number since it is divisible by the number (20) 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 20149920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39312000).

20149920 is an abundant number, since it is smaller than the sum of its proper divisors (58474080).

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

20149920 is a wasteful number, since it uses less digits than its factorization.

20149920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2027 (or 2016 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 27.

The square root of 20149920 is about 4488.8662265655. The cubic root of 20149920 is about 272.1183164618.

The spelling of 20149920 in words is "twenty million, one hundred forty-nine thousand, nine hundred twenty".