22021620 has 24 divisors (see below), whose sum is σ = 61660704. Its totient is φ = 5872416.

The previous prime is 22021591. The next prime is 22021621. The reversal of 22021620 is 2612022.

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 22021620.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22021621) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 183454 + ... + 183573.

It is an arithmetic number, because the mean of its divisors is an integer number (2569196).

Almost surely, 2^22021620 is an apocalyptic number.

22021620 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

22021620 is an abundant number, since it is smaller than the sum of its proper divisors (39639084).

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

22021620 is a wasteful number, since it uses less digits than its factorization.

22021620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 367039 (or 367037 counting only the distinct ones).

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

The square root of 22021620 is about 4692.7198936225. The cubic root of 22021620 is about 280.2956910301.

Adding to 22021620 its reverse (2612022), we get a palindrome (24633642).

The spelling of 22021620 in words is "twenty-two million, twenty-one thousand, six hundred twenty".