22021989 has 8 divisors (see below), whose sum is σ = 32032032. Its totient is φ = 13346640.

The previous prime is 22021981. The next prime is 22022009. The reversal of 22021989 is 98912022.

It is a happy number.

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

It is not a de Polignac number, because 22021989 - 2³ = 22021981 is a prime.

It is a super-2 number, since 2×22021989² = 969935999032242, which contains 22 as substring.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Harshad number since it is a multiple of its sum of digits (33), and also a Moran number because the ratio is a prime number: 667333 = 22021989 / (2 + 2 + 0 + 2 + 1 + 9 + 8 + 9).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22021981) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 333634 + ... + 333699.

It is an arithmetic number, because the mean of its divisors is an integer number (4004004).

Almost surely, 2^22021989 is an apocalyptic number.

It is an amenable number.

22021989 is a deficient number, since it is larger than the sum of its proper divisors (10010043).

22021989 is a wasteful number, since it uses less digits than its factorization.

22021989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 667347.

The product of its (nonzero) digits is 5184, while the sum is 33.

The square root of 22021989 is about 4692.7592096761. The cubic root of 22021989 is about 280.2972565905.

Adding to 22021989 its sum of digits (33), we get a palindrome (22022022).

The spelling of 22021989 in words is "twenty-two million, twenty-one thousand, nine hundred eighty-nine".