22021081 has 4 divisors (see below), whose sum is σ = 22072372. Its totient is φ = 21969792.

The previous prime is 22021049. The next prime is 22021093. The reversal of 22021081 is 18012022.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1690000 + 20331081 = 1300^2 + 4509^2 .

It is a cyclic number.

It is not a de Polignac number, because 22021081 - 2⁵ = 22021049 is a prime.

It is a super-2 number, since 2×22021081² = 969856016817122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (22021981) 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, 24996 + ... + 25861.

It is an arithmetic number, because the mean of its divisors is an integer number (5518093).

Almost surely, 2^22021081 is an apocalyptic number.

It is an amenable number.

22021081 is a deficient number, since it is larger than the sum of its proper divisors (51291).

22021081 is an equidigital number, since it uses as much as digits as its factorization.

22021081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51290.

The product of its (nonzero) digits is 64, while the sum is 16.

The square root of 22021081 is about 4692.6624638898. The cubic root of 22021081 is about 280.2934041773.

The spelling of 22021081 in words is "twenty-two million, twenty-one thousand, eighty-one".