21303132 has 12 divisors (see below), whose sum is σ = 49707336. Its totient is φ = 7101040.

The previous prime is 21303131. The next prime is 21303137. The reversal of 21303132 is 23130312.

It is a tau number, because it is divible by the number of its divisors (12).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21303131) 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, 887619 + ... + 887642.

It is an arithmetic number, because the mean of its divisors is an integer number (4142278).

Almost surely, 2^21303132 is an apocalyptic number.

It is an amenable number.

21303132 is an abundant number, since it is smaller than the sum of its proper divisors (28404204).

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

21303132 is a wasteful number, since it uses less digits than its factorization.

21303132 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1775268 (or 1775266 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 15.

The square root of 21303132 is about 4615.5316053517. The cubic root of 21303132 is about 277.2135702124.

Adding to 21303132 its reverse (23130312), we get a palindrome (44433444).

The spelling of 21303132 in words is "twenty-one million, three hundred three thousand, one hundred thirty-two".