22545581 has 2 divisors, whose sum is σ = 22545582. Its totient is φ = 22545580.

The previous prime is 22545577. The next prime is 22545583. The reversal of 22545581 is 18554522.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19624900 + 2920681 = 4430^2 + 1709^2 .

It is a cyclic number.

It is not a de Polignac number, because 22545581 - 2² = 22545577 is a prime.

It is a super-2 number, since 2×22545581² = 1016606445255122, which contains 22 as substring.

Together with 22545583, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (22545583) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11272790 + 11272791.

It is an arithmetic number, because the mean of its divisors is an integer number (11272791).

Almost surely, 2^22545581 is an apocalyptic number.

It is an amenable number.

22545581 is a deficient number, since it is larger than the sum of its proper divisors (1).

22545581 is an equidigital number, since it uses as much as digits as its factorization.

22545581 is an evil number, because the sum of its binary digits is even.

The product of its digits is 16000, while the sum is 32.

The square root of 22545581 is about 4748.2187186354. The cubic root of 22545581 is about 282.5013172466.

The spelling of 22545581 in words is "twenty-two million, five hundred forty-five thousand, five hundred eighty-one".