20123131021220 has 12 divisors (see below), whose sum is σ = 42258575144604. Its totient is φ = 8049252408480.

The previous prime is 20123131021163. The next prime is 20123131021267. The reversal of 20123131021220 is 2212013132102.

It can be written as a sum of positive squares in 2 ways, for example, as 15132053320036 + 4991077701184 = 3889994^2 + 2234072^2 .

It is a Harshad number since it is a multiple of its sum of digits (20), and also a Moran number because the ratio is a prime number: 1006156551061 = 20123131021220 / (2 + 0 + 1 + 2 + 3 + 1 + 3 + 1 + 0 + 2 + 1 + 2 + 2 + 0).

It is a junction number, because it is equal to n+sod(n) for n = 20123131021192 and 20123131021201.

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, 503078275511 + ... + 503078275550.

It is an arithmetic number, because the mean of its divisors is an integer number (3521547928717).

Almost surely, 2^{20123131021220} is an apocalyptic number.

20123131021220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20123131021220 is an abundant number, since it is smaller than the sum of its proper divisors (22135444123384).

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

20123131021220 is a wasteful number, since it uses less digits than its factorization.

20123131021220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1006156551070 (or 1006156551068 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 20.

Adding to 20123131021220 its reverse (2212013132102), we get a palindrome (22335144153322).

The spelling of 20123131021220 in words is "twenty trillion, one hundred twenty-three billion, one hundred thirty-one million, twenty-one thousand, two hundred twenty".