20212920 has 192 divisors, whose sum is σ = 80982720. Its totient is φ = 4257792.

The previous prime is 20212909. The next prime is 20212931. The reversal of 20212920 is 2921202.

It is an interprime number because it is at equal distance from previous prime (20212909) and next prime (20212931).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 20212893 and 20212902.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 32452 + ... + 33068.

It is an arithmetic number, because the mean of its divisors is an integer number (421785).

Almost surely, 2^20212920 is an apocalyptic number.

20212920 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 20212920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40491360).

20212920 is an abundant number, since it is smaller than the sum of its proper divisors (60769800).

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

20212920 is a wasteful number, since it uses less digits than its factorization.

20212920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 654 (or 647 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

The square root of 20212920 is about 4495.8781122268. The cubic root of 20212920 is about 272.4016197902.

The spelling of 20212920 in words is "twenty million, two hundred twelve thousand, nine hundred twenty".