22256561 has 4 divisors (see below), whose sum is σ = 22281252. Its totient is φ = 22231872.

The previous prime is 22256551. The next prime is 22256569. The reversal of 22256561 is 16565222.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 7480225 + 14776336 = 2735^2 + 3844^2 .

It is a cyclic number.

It is not a de Polignac number, because 22256561 - 2²² = 18062257 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (22256569) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10940 + ... + 12813.

It is an arithmetic number, because the mean of its divisors is an integer number (5570313).

Almost surely, 2^22256561 is an apocalyptic number.

It is an amenable number.

22256561 is a deficient number, since it is larger than the sum of its proper divisors (24691).

22256561 is an equidigital number, since it uses as much as digits as its factorization.

22256561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24690.

The product of its digits is 7200, while the sum is 29.

The square root of 22256561 is about 4717.6859793759. The cubic root of 22256561 is about 281.2889594754.

The spelling of 22256561 in words is "twenty-two million, two hundred fifty-six thousand, five hundred sixty-one".