22109581 has 8 divisors (see below), whose sum is σ = 23912504. Its totient is φ = 20321280.

The previous prime is 22109579. The next prime is 22109617. The reversal of 22109581 is 18590122.

It can be written as a sum of positive squares in 4 ways, for example, as 9400356 + 12709225 = 3066^2 + 3565^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 22109581 - 2¹ = 22109579 is a prime.

It is a super-2 number, since 2×22109581² = 977667143991122, 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 (22109551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 396 + ... + 6661.

It is an arithmetic number, because the mean of its divisors is an integer number (2989063).

Almost surely, 2^22109581 is an apocalyptic number.

It is an amenable number.

22109581 is a deficient number, since it is larger than the sum of its proper divisors (1802923).

22109581 is a wasteful number, since it uses less digits than its factorization.

22109581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7311.

The product of its (nonzero) digits is 1440, while the sum is 28.

The square root of 22109581 is about 4702.0826236892. The cubic root of 22109581 is about 280.6683904546.

The spelling of 22109581 in words is "twenty-two million, one hundred nine thousand, five hundred eighty-one".