20201920 has 28 divisors (see below), whose sum is σ = 48106584. Its totient is φ = 8080640.

The previous prime is 20201917. The next prime is 20201939. The reversal of 20201920 is 2910202.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (16).

It is a junction number, because it is equal to n+sod(n) for n = 20201894 and 20201903.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 31246 + ... + 31885.

Almost surely, 2^20201920 is an apocalyptic number.

20201920 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20201920 is an abundant number, since it is smaller than the sum of its proper divisors (27904664).

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

20201920 is an equidigital number, since it uses as much as digits as its factorization.

20201920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63148 (or 63138 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 16.

The square root of 20201920 is about 4494.6546029701. The cubic root of 20201920 is about 272.3521965906.

The spelling of 20201920 in words is "twenty million, two hundred one thousand, nine hundred twenty".