22640561 has 6 divisors (see below), whose sum is σ = 23449062. Its totient is φ = 21859040.

The previous prime is 22640557. The next prime is 22640581. The reversal of 22640561 is 16504622.

It can be written as a sum of positive squares in 3 ways, for example, as 11182336 + 11458225 = 3344^2 + 3385^2 .

It is not a de Polignac number, because 22640561 - 2² = 22640557 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 22640561.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22640581) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 12620 + ... + 14301.

It is an arithmetic number, because the mean of its divisors is an integer number (3908177).

Almost surely, 2^22640561 is an apocalyptic number.

It is an amenable number.

22640561 is a deficient number, since it is larger than the sum of its proper divisors (808501).

22640561 is an equidigital number, since it uses as much as digits as its factorization.

22640561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26979 (or 26950 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 26.

The square root of 22640561 is about 4758.2098524550. The cubic root of 22640561 is about 282.8974685487.

The spelling of 22640561 in words is "twenty-two million, six hundred forty thousand, five hundred sixty-one".