22775981 has 2 divisors, whose sum is σ = 22775982. Its totient is φ = 22775980.

The previous prime is 22775899. The next prime is 22775989. The reversal of 22775981 is 18957722.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 22705225 + 70756 = 4765^2 + 266^2 .

It is a cyclic number.

It is not a de Polignac number, because 22775981 - 2¹⁸ = 22513837 is a prime.

It is a super-2 number, since 2×22775981² = 1037490621024722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (22775989) 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 as a sum of consecutive naturals, namely, 11387990 + 11387991.

It is an arithmetic number, because the mean of its divisors is an integer number (11387991).

Almost surely, 2^22775981 is an apocalyptic number.

It is an amenable number.

22775981 is a deficient number, since it is larger than the sum of its proper divisors (1).

22775981 is an equidigital number, since it uses as much as digits as its factorization.

22775981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 70560, while the sum is 41.

The square root of 22775981 is about 4772.4187787746. The cubic root of 22775981 is about 283.4603793181.

The spelling of 22775981 in words is "twenty-two million, seven hundred seventy-five thousand, nine hundred eighty-one".