22021211220 has 96 divisors (see below), whose sum is σ = 62429324160. Its totient is φ = 5799444480.

The previous prime is 22021211197. The next prime is 22021211221. The reversal of 22021211220 is 2211212022.

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 22021211220.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22021211221) 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, 1602780 + ... + 1616460.

It is an arithmetic number, because the mean of its divisors is an integer number (650305460).

Almost surely, 2^22021211220 is an apocalyptic number.

22021211220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 22021211220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31214662080).

22021211220 is an abundant number, since it is smaller than the sum of its proper divisors (40408112940).

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

22021211220 is a wasteful number, since it uses less digits than its factorization.

22021211220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14025 (or 14023 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 22021211220 its reverse (2211212022), we get a palindrome (24232423242).

The spelling of 22021211220 in words is "twenty-two billion, twenty-one million, two hundred eleven thousand, two hundred twenty".