22088021 has 4 divisors (see below), whose sum is σ = 22108332. Its totient is φ = 22067712.

The previous prime is 22088009. The next prime is 22088047. The reversal of 22088021 is 12088022.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12088022 = 2 ⋅6044011.

It can be written as a sum of positive squares in 2 ways, for example, as 7761796 + 14326225 = 2786^2 + 3785^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-22088021 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22088071) 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, 8426 + ... + 10731.

It is an arithmetic number, because the mean of its divisors is an integer number (5527083).

Almost surely, 2^22088021 is an apocalyptic number.

It is an amenable number.

22088021 is a deficient number, since it is larger than the sum of its proper divisors (20311).

22088021 is a wasteful number, since it uses less digits than its factorization.

22088021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20310.

The product of its (nonzero) digits is 512, while the sum is 23.

The square root of 22088021 is about 4699.7894633696. The cubic root of 22088021 is about 280.5771301921.

Subtracting from 22088021 its reverse (12088022), we obtain a palindrome (9999999).

The spelling of 22088021 in words is "twenty-two million, eighty-eight thousand, twenty-one".