22051581 has 4 divisors (see below), whose sum is σ = 29402112. Its totient is φ = 14701052.

The previous prime is 22051573. The next prime is 22051583. The reversal of 22051581 is 18515022.

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 22051581 - 2³ = 22051573 is a prime.

It is a super-2 number, since 2×22051581² = 972544449199122, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22051583) 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, 3675261 + ... + 3675266.

It is an arithmetic number, because the mean of its divisors is an integer number (7350528).

Almost surely, 2^22051581 is an apocalyptic number.

It is an amenable number.

22051581 is a deficient number, since it is larger than the sum of its proper divisors (7350531).

22051581 is an equidigital number, since it uses as much as digits as its factorization.

22051581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7350530.

The product of its (nonzero) digits is 800, while the sum is 24.

The square root of 22051581 is about 4695.9110937069. The cubic root of 22051581 is about 280.4227500072.

The spelling of 22051581 in words is "twenty-two million, fifty-one thousand, five hundred eighty-one".