22021940 has 12 divisors (see below), whose sum is σ = 46246116. Its totient is φ = 8808768.

The previous prime is 22021913. The next prime is 22021943. The reversal of 22021940 is 4912022.

It can be written as a sum of positive squares in 2 ways, for example, as 3857296 + 18164644 = 1964^2 + 4262^2 .

It is a Harshad number since it is a multiple of its sum of digits (20), and also a Moran number because the ratio is a prime number: 1101097 = 22021940 / (2 + 2 + 0 + 2 + 1 + 9 + 4 + 0).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22021943) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 550529 + ... + 550568.

It is an arithmetic number, because the mean of its divisors is an integer number (3853843).

Almost surely, 2^22021940 is an apocalyptic number.

22021940 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

22021940 is an abundant number, since it is smaller than the sum of its proper divisors (24224176).

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

22021940 is a wasteful number, since it uses less digits than its factorization.

22021940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1101106 (or 1101104 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 20.

The square root of 22021940 is about 4692.7539888641. The cubic root of 22021940 is about 280.2970486987.

Adding to 22021940 its reverse (4912022), we get a palindrome (26933962).

The spelling of 22021940 in words is "twenty-two million, twenty-one thousand, nine hundred forty".