21002110031220 has 96 divisors (see below), whose sum is σ = 59865684633216. Its totient is φ = 5500513075200.

The previous prime is 21002110031219. The next prime is 21002110031323. The reversal of 21002110031220 is 2213001120012.

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 21002110031220.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 13010901 + ... + 14535740.

It is an arithmetic number, because the mean of its divisors is an integer number (623600881596).

Almost surely, 2^{21002110031220} is an apocalyptic number.

21002110031220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21002110031220 is an abundant number, since it is smaller than the sum of its proper divisors (38863574601996).

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

21002110031220 is a wasteful number, since it uses less digits than its factorization.

21002110031220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27546881 (or 27546879 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 15.

Adding to 21002110031220 its reverse (2213001120012), we get a palindrome (23215111151232).

The spelling of 21002110031220 in words is "twenty-one trillion, two billion, one hundred ten million, thirty-one thousand, two hundred twenty".