21975822 has 24 divisors (see below), whose sum is σ = 51943320. Its totient is φ = 6659280.

The previous prime is 21975809. The next prime is 21975829. The reversal of 21975822 is 22857912.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21975829) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 55297 + ... + 55692.

It is an arithmetic number, because the mean of its divisors is an integer number (2164305).

Almost surely, 2^21975822 is an apocalyptic number.

21975822 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21975822 is an abundant number, since it is smaller than the sum of its proper divisors (29967498).

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

21975822 is a wasteful number, since it uses less digits than its factorization.

21975822 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 111008 (or 111005 counting only the distinct ones).

The product of its digits is 20160, while the sum is 36.

The square root of 21975822 is about 4687.8376678379. The cubic root of 21975822 is about 280.1012473984.

The spelling of 21975822 in words is "twenty-one million, nine hundred seventy-five thousand, eight hundred twenty-two".