21132337 has 4 divisors (see below), whose sum is σ = 21141540. Its totient is φ = 21123136.

The previous prime is 21132317. The next prime is 21132341. The reversal of 21132337 is 73323112.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 9511056 + 11621281 = 3084^2 + 3409^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21132337 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21132317) 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, 2013 + ... + 6805.

It is an arithmetic number, because the mean of its divisors is an integer number (5285385).

Almost surely, 2^21132337 is an apocalyptic number.

It is an amenable number.

21132337 is a deficient number, since it is larger than the sum of its proper divisors (9203).

21132337 is an equidigital number, since it uses as much as digits as its factorization.

21132337 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9202.

The product of its digits is 756, while the sum is 22.

The square root of 21132337 is about 4596.9921687991. The cubic root of 21132337 is about 276.4707406252.

Adding to 21132337 its reverse (73323112), we get a palindrome (94455449).

The spelling of 21132337 in words is "twenty-one million, one hundred thirty-two thousand, three hundred thirty-seven".