20437920 has 240 divisors, whose sum is σ = 76839840. Its totient is φ = 5101056.

The previous prime is 20437909. The next prime is 20437933. The reversal of 20437920 is 2973402.

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 246199 + ... + 246281.

It is an arithmetic number, because the mean of its divisors is an integer number (320166).

Almost surely, 2^20437920 is an apocalyptic number.

20437920 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 20437920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38419920).

20437920 is an abundant number, since it is smaller than the sum of its proper divisors (56401920).

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

20437920 is a wasteful number, since it uses less digits than its factorization.

20437920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 129 (or 112 counting only the distinct ones).

The product of its (nonzero) digits is 3024, while the sum is 27.

The square root of 20437920 is about 4520.8317818738. The cubic root of 20437920 is about 273.4086381183.

The spelling of 20437920 in words is "twenty million, four hundred thirty-seven thousand, nine hundred twenty".