21282 has 8 divisors (see below), whose sum is σ = 42576. Its totient is φ = 7092.

The previous prime is 21277. The next prime is 21283. The reversal of 21282 is 28212.

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

21282 is an admirable number.

It is a nialpdrome in base 16.

It is not an unprimeable number, because it can be changed into a prime (21283) 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, 1768 + ... + 1779.

It is an arithmetic number, because the mean of its divisors is an integer number (5322).

2²¹²⁸² is an apocalyptic number.

21282 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

It is a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21288).

21282 is a wasteful number, since it uses less digits than its factorization.

21282 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3552.

The product of its digits is 64, while the sum is 15.

The square root of 21282 is about 145.8835151756. The cubic root of 21282 is about 27.7121877666.

Adding to 21282 its reverse (28212), we get a palindrome (49494).

It can be divided in two parts, 21 and 282, that added together give a palindrome (303).

The spelling of 21282 in words is "twenty-one thousand, two hundred eighty-two".