22981 has 8 divisors (see below), whose sum is σ = 27200.
Its totient is φ = 19404.
The previous prime is 22973. The next prime is 22993. The reversal of 22981 is 18922.
It is not a de Polignac number, because 22981 - 23 = 22973 is a prime.
It is a super-2 number, since 2×229812 = 1056252722, which contains 22 as substring.
It is a Duffinian number.
22981 is a lucky number.
It is a congruent number.
It is not an unprimeable number, because it can be changed into a prime (22901) 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, 310 + ... + 376.
It is an arithmetic number, because the mean of its divisors is an integer number (3400).
222981 is an apocalyptic number.
It is an amenable number.
22981 is a deficient number, since it is larger than the sum of its proper divisors (4219).
22981 is an frugal number, since it uses more digits than its factorization.
22981 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 88 (or 74 counting only the distinct ones).
The product of its digits is 288, while the sum is 22.
The square root of 22981 is about 151.5948547940.
The cubic root of 22981 is about 28.4308367031.
The spelling of 22981 in words is "twenty-two thousand, nine hundred eighty-one".