22208581 has 4 divisors (see below), whose sum is σ = 22681152. Its totient is φ = 21736012.

The previous prime is 22208573. The next prime is 22208609. The reversal of 22208581 is 18580222.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 22208581 - 2³ = 22208573 is a prime.

It is a super-2 number, since 2×22208581² = 986442140067122, 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 (22208281) 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, 236215 + ... + 236308.

It is an arithmetic number, because the mean of its divisors is an integer number (5670288).

Almost surely, 2^22208581 is an apocalyptic number.

It is an amenable number.

22208581 is a deficient number, since it is larger than the sum of its proper divisors (472571).

22208581 is an equidigital number, since it uses as much as digits as its factorization.

22208581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 472570.

The product of its (nonzero) digits is 2560, while the sum is 28.

The square root of 22208581 is about 4712.5981156895. The cubic root of 22208581 is about 281.0866827300.

It can be divided in two parts, 2220 and 8581, that added together give a palindrome (10801).

The spelling of 22208581 in words is "twenty-two million, two hundred eight thousand, five hundred eighty-one".