21103022220 has 96 divisors (see below), whose sum is σ = 71083891200. Its totient is φ = 4569675264.

The previous prime is 21103022207. The next prime is 21103022221. The reversal of 21103022220 is 2222030112.

It is a happy number.

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 21103022220.

It is not an unprimeable number, because it can be changed into a prime (21103022221) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1314265 + ... + 1330224.

It is an arithmetic number, because the mean of its divisors is an integer number (740457200).

Almost surely, 2^21103022220 is an apocalyptic number.

21103022220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21103022220 is an abundant number, since it is smaller than the sum of its proper divisors (49980868980).

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

21103022220 is a wasteful number, since it uses less digits than its factorization.

21103022220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2644527 (or 2644525 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 15.

Adding to 21103022220 its reverse (2222030112), we get a palindrome (23325052332).

The spelling of 21103022220 in words is "twenty-one billion, one hundred three million, twenty-two thousand, two hundred twenty".