22015681 has 2 divisors, whose sum is σ = 22015682. Its totient is φ = 22015680.

The previous prime is 22015657. The next prime is 22015687. The reversal of 22015681 is 18651022.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12895281 + 9120400 = 3591^2 + 3020^2 .

It is a cyclic number.

It is not a de Polignac number, because 22015681 - 2¹⁷ = 21884609 is a prime.

It is a super-2 number, since 2×22015681² = 969380419787522, which contains 22 as substring.

It is equal to p_1390192 and since 22015681 and 1390192 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (22015687) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11007840 + 11007841.

It is an arithmetic number, because the mean of its divisors is an integer number (11007841).

Almost surely, 2^22015681 is an apocalyptic number.

It is an amenable number.

22015681 is a deficient number, since it is larger than the sum of its proper divisors (1).

22015681 is an equidigital number, since it uses as much as digits as its factorization.

22015681 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 960, while the sum is 25.

The square root of 22015681 is about 4692.0870622784. The cubic root of 22015681 is about 280.2704911616.

The spelling of 22015681 in words is "twenty-two million, fifteen thousand, six hundred eighty-one".