22655981 has 2 divisors, whose sum is σ = 22655982. Its totient is φ = 22655980.

The previous prime is 22655921. The next prime is 22656001. The reversal of 22655981 is 18955622.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19624900 + 3031081 = 4430^2 + 1741^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-22655981 is a prime.

It is a super-2 number, since 2×22655981² = 1026586950144722, which contains 22 as substring.

It is equal to p_1427888 and since 22655981 and 1427888 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (22655921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11327990 + 11327991.

It is an arithmetic number, because the mean of its divisors is an integer number (11327991).

Almost surely, 2^22655981 is an apocalyptic number.

It is an amenable number.

22655981 is a deficient number, since it is larger than the sum of its proper divisors (1).

22655981 is an equidigital number, since it uses as much as digits as its factorization.

22655981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 43200, while the sum is 38.

The square root of 22655981 is about 4759.8299339367. The cubic root of 22655981 is about 282.9616791041.

The spelling of 22655981 in words is "twenty-two million, six hundred fifty-five thousand, nine hundred eighty-one".