21100313220 has 96 divisors (see below), whose sum is σ = 67542843648. Its totient is φ = 4821368832.

The previous prime is 21100313197. The next prime is 21100313231. The reversal of 21100313220 is 2231300112.

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 21100313220.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1738212 + ... + 1750308.

It is an arithmetic number, because the mean of its divisors is an integer number (703571288).

Almost surely, 2^21100313220 is an apocalyptic number.

21100313220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21100313220 is an abundant number, since it is smaller than the sum of its proper divisors (46442530428).

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

21100313220 is a wasteful number, since it uses less digits than its factorization.

21100313220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16269 (or 16267 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 15.

Adding to 21100313220 its reverse (2231300112), we get a palindrome (23331613332).

The spelling of 21100313220 in words is "twenty-one billion, one hundred million, three hundred thirteen thousand, two hundred twenty".