20312020 has 12 divisors (see below), whose sum is σ = 42655284. Its totient is φ = 8124800.

The previous prime is 20311981. The next prime is 20312021. The reversal of 20312020 is 2021302.

It can be written as a sum of positive squares in 2 ways, for example, as 8928144 + 11383876 = 2988^2 + 3374^2 .

It is a Harshad number since it is a multiple of its sum of digits (10).

It is a junction number, because it is equal to n+sod(n) for n = 20311988 and 20312006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20312021) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 507781 + ... + 507820.

It is an arithmetic number, because the mean of its divisors is an integer number (3554607).

Almost surely, 2^20312020 is an apocalyptic number.

20312020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20312020 is an abundant number, since it is smaller than the sum of its proper divisors (22343264).

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

20312020 is a wasteful number, since it uses less digits than its factorization.

20312020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1015610 (or 1015608 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 10.

The square root of 20312020 is about 4506.8858427966. The cubic root of 20312020 is about 272.8460715439.

Adding to 20312020 its reverse (2021302), we get a palindrome (22333322).

The spelling of 20312020 in words is "twenty million, three hundred twelve thousand, twenty".