21302 has 4 divisors (see below), whose sum is σ = 31956. Its totient is φ = 10650.

The previous prime is 21283. The next prime is 21313. The reversal of 21302 is 20312.

It is a semiprime because it is the product of two primes.

It is a self number, because there is not a number n which added to its sum of digits gives 21302.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5324 + ... + 5327.

It is an arithmetic number, because the mean of its divisors is an integer number (7989).

2²¹³⁰² is an apocalyptic number.

21302 is a deficient number, since it is larger than the sum of its proper divisors (10654).

21302 is a wasteful number, since it uses less digits than its factorization.

21302 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10653.

The product of its (nonzero) digits is 12, while the sum is 8.

The square root of 21302 is about 145.9520469195. The cubic root of 21302 is about 27.7208659959.

Adding to 21302 its reverse (20312), we get a palindrome (41614).

Subtracting from 21302 its reverse (20312), we obtain a triangular number (990 = T₄₄).

It can be divided in two parts, 21 and 302, that added together give a palindrome (323).

The spelling of 21302 in words is "twenty-one thousand, three hundred two", and thus it is an iban number.