22561581 has 8 divisors (see below), whose sum is σ = 34379584. Its totient is φ = 12892320.

The previous prime is 22561577. The next prime is 22561613. The reversal of 22561581 is 18516522.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 22561581 - 2² = 22561577 is a prime.

It is a super-2 number, since 2×22561581² = 1018049874439122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22561181) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 537160 + ... + 537201.

It is an arithmetic number, because the mean of its divisors is an integer number (4297448).

Almost surely, 2^22561581 is an apocalyptic number.

22561581 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

22561581 is a deficient number, since it is larger than the sum of its proper divisors (11818003).

22561581 is a wasteful number, since it uses less digits than its factorization.

22561581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1074371.

The product of its digits is 4800, while the sum is 30.

The square root of 22561581 is about 4749.9032621728. The cubic root of 22561581 is about 282.5681293379.

The spelling of 22561581 in words is "twenty-two million, five hundred sixty-one thousand, five hundred eighty-one".