21021120110220 has 96 divisors (see below), whose sum is σ = 60183103861440. Its totient is φ = 5480292679680.

The previous prime is 21021120110191. The next prime is 21021120110279. The reversal of 21021120110220 is 2201102112012.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 21021120110220.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 10868725 + ... + 12655884.

It is an arithmetic number, because the mean of its divisors is an integer number (626907331890).

Almost surely, 2^{21021120110220} is an apocalyptic number.

21021120110220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21021120110220 is an abundant number, since it is smaller than the sum of its proper divisors (39161983751220).

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

21021120110220 is a wasteful number, since it uses less digits than its factorization.

21021120110220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23524955 (or 23524953 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 21021120110220 its reverse (2201102112012), we get a palindrome (23222222222232).

The spelling of 21021120110220 in words is "twenty-one trillion, twenty-one billion, one hundred twenty million, one hundred ten thousand, two hundred twenty".