20022561 has 24 divisors (see below), whose sum is σ = 32789120. Its totient is φ = 11671776.

The previous prime is 20022553. The next prime is 20022571. The reversal of 20022561 is 16522002.

It is not a de Polignac number, because 20022561 - 2³ = 20022553 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20022511) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2281 + ... + 6726.

Almost surely, 2^20022561 is an apocalyptic number.

It is an amenable number.

20022561 is a deficient number, since it is larger than the sum of its proper divisors (12766559).

20022561 is a wasteful number, since it uses less digits than its factorization.

20022561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9045 (or 9042 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 20022561 is about 4474.6576405352. The cubic root of 20022561 is about 271.5437899312.

Adding to 20022561 its reverse (16522002), we get a palindrome (36544563).

The spelling of 20022561 in words is "twenty million, twenty-two thousand, five hundred sixty-one".