21592 has 8 divisors (see below), whose sum is σ = 40500. Its totient is φ = 10792.

The previous prime is 21589. The next prime is 21599. The reversal of 21592 is 29512.

It is a tau number, because it is divible by the number of its divisors (8).

It is a zygodrome in base 7.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21599) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1342 + ... + 1357.

2²¹⁵⁹² is an apocalyptic number.

It is an amenable number.

21592 is a deficient number, since it is larger than the sum of its proper divisors (18908).

21592 is a wasteful number, since it uses less digits than its factorization.

21592 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2705 (or 2701 counting only the distinct ones).

The product of its digits is 180, while the sum is 19.

The square root of 21592 is about 146.9421654938. The cubic root of 21592 is about 27.8460943632.

Subtracting from 21592 its product of digits (180), we obtain a palindrome (21412).

The spelling of 21592 in words is "twenty-one thousand, five hundred ninety-two".