22161322561 has 24 divisors (see below), whose sum is σ = 25927758720. Its totient is φ = 18886442400.

The previous prime is 22161322517. The next prime is 22161322577. The reversal of 22161322561 is 16522316122.

It is not a de Polignac number, because 22161322561 - 2¹⁷ = 22161191489 is a prime.

It is a super-2 number, since 2×22161322561² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (22161322591) 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, 11019046 + ... + 11021056.

It is an arithmetic number, because the mean of its divisors is an integer number (1080323280).

Almost surely, 2^22161322561 is an apocalyptic number.

It is an amenable number.

22161322561 is a deficient number, since it is larger than the sum of its proper divisors (3766436159).

22161322561 is a wasteful number, since it uses less digits than its factorization.

22161322561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3205 (or 3198 counting only the distinct ones).

The product of its digits is 8640, while the sum is 31.

Adding to 22161322561 its reverse (16522316122), we get a palindrome (38683638683).

The spelling of 22161322561 in words is "twenty-two billion, one hundred sixty-one million, three hundred twenty-two thousand, five hundred sixty-one".