22161989 has 4 divisors (see below), whose sum is σ = 22365420. Its totient is φ = 21958560.

The previous prime is 22161977. The next prime is 22161991. The reversal of 22161989 is 98916122.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 98916122 = 2 ⋅49458061.

It can be written as a sum of positive squares in 2 ways, for example, as 16120225 + 6041764 = 4015^2 + 2458^2 .

It is a cyclic number.

It is not a de Polignac number, because 22161989 - 2⁴ = 22161973 is a prime.

It is a super-2 number, since 2×22161989² = 982307512872242, 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 (22161929) 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, 101552 + ... + 101769.

It is an arithmetic number, because the mean of its divisors is an integer number (5591355).

Almost surely, 2^22161989 is an apocalyptic number.

It is an amenable number.

22161989 is a deficient number, since it is larger than the sum of its proper divisors (203431).

22161989 is a wasteful number, since it uses less digits than its factorization.

22161989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 203430.

The product of its digits is 15552, while the sum is 38.

The square root of 22161989 is about 4707.6521749169. The cubic root of 22161989 is about 280.8899785846.

The spelling of 22161989 in words is "twenty-two million, one hundred sixty-one thousand, nine hundred eighty-nine".