21131310220220 has 12 divisors (see below), whose sum is σ = 44375751462504. Its totient is φ = 8452524088080.

The previous prime is 21131310220177. The next prime is 21131310220309. The reversal of 21131310220220 is 2202201313112.

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: 1056565511011 = 21131310220220 / (2 + 1 + 1 + 3 + 1 + 3 + 1 + 0 + 2 + 2 + 0 + 2 + 2 + 0).

It is a junction number, because it is equal to n+sod(n) for n = 21131310220192 and 21131310220201.

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, 528282755486 + ... + 528282755525.

It is an arithmetic number, because the mean of its divisors is an integer number (3697979288542).

Almost surely, 2^{21131310220220} is an apocalyptic number.

21131310220220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21131310220220 is an abundant number, since it is smaller than the sum of its proper divisors (23244441242284).

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

21131310220220 is a wasteful number, since it uses less digits than its factorization.

21131310220220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1056565511020 (or 1056565511018 counting only the distinct ones).

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

Adding to 21131310220220 its reverse (2202201313112), we get a palindrome (23333511533332).

The spelling of 21131310220220 in words is "twenty-one trillion, one hundred thirty-one billion, three hundred ten million, two hundred twenty thousand, two hundred twenty".