20022581 has 4 divisors (see below), whose sum is σ = 20893152. Its totient is φ = 19152012.

The previous prime is 20022577. The next prime is 20022593. The reversal of 20022581 is 18522002.

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 20022581 - 2² = 20022577 is a prime.

It is a super-2 number, since 2×20022581² = 801807499803122, 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 (20022511) 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 3 ways as a sum of consecutive naturals, for example, 435251 + ... + 435296.

It is an arithmetic number, because the mean of its divisors is an integer number (5223288).

Almost surely, 2^20022581 is an apocalyptic number.

It is an amenable number.

20022581 is a deficient number, since it is larger than the sum of its proper divisors (870571).

20022581 is an equidigital number, since it uses as much as digits as its factorization.

20022581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 870570.

The product of its (nonzero) digits is 320, while the sum is 20.

The square root of 20022581 is about 4474.6598753425. The cubic root of 20022581 is about 271.5438803438.

Adding to 20022581 its reverse (18522002), we get a palindrome (38544583).

The spelling of 20022581 in words is "twenty million, twenty-two thousand, five hundred eighty-one".