22021020 has 72 divisors (see below), whose sum is σ = 76343904. Its totient is φ = 5033088.

The previous prime is 22021009. The next prime is 22021049. The reversal of 22021020 is 2012022.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 22020993 and 22021011.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 7479 + ... + 9998.

It is an arithmetic number, because the mean of its divisors is an integer number (1060332).

Almost surely, 2^22021020 is an apocalyptic number.

22021020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

22021020 is an abundant number, since it is smaller than the sum of its proper divisors (54322884).

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

22021020 is a wasteful number, since it uses less digits than its factorization.

22021020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17499 (or 17494 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 9.

The square root of 22021020 is about 4692.6559643767. The cubic root of 22021020 is about 280.2931453660.

Adding to 22021020 its reverse (2012022), we get a palindrome (24033042).

The spelling of 22021020 in words is "twenty-two million, twenty-one thousand, twenty".