21100331131020 has 72 divisors (see below), whose sum is σ = 65492810759376. Its totient is φ = 5495900199552.

The previous prime is 21100331130973. The next prime is 21100331131021. The reversal of 21100331131020 is 2013113300112.

21100331131020 is a `hidden beast` number, since 2 + 1 + 1 + 0 + 0 + 331 + 1 + 310 + 20 = 666.

21100331131020 is digitally balanced in base 5, because in such base it contains all the possibile digits an equal number of times.

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 = 21100331130984 and 21100331131002.

It is not an unprimeable number, because it can be changed into a prime (21100331131021) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1363062747 + ... + 1363078226.

It is an arithmetic number, because the mean of its divisors is an integer number (909622371658).

Almost surely, 2^{21100331131020} is an apocalyptic number.

21100331131020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21100331131020 is an abundant number, since it is smaller than the sum of its proper divisors (44392479628356).

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

21100331131020 is a wasteful number, since it uses less digits than its factorization.

21100331131020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2726141031 (or 2726141026 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 18.

Adding to 21100331131020 its reverse (2013113300112), we get a palindrome (23113444431132).

The spelling of 21100331131020 in words is "twenty-one trillion, one hundred billion, three hundred thirty-one million, one hundred thirty-one thousand, twenty".