21332123 has 4 divisors (see below), whose sum is σ = 22020288. Its totient is φ = 20643960.

The previous prime is 21332119. The next prime is 21332141. The reversal of 21332123 is 32123312.

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

It is a cyclic number.

It is not a de Polignac number, because 21332123 - 2² = 21332119 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21332153) 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, 344036 + ... + 344097.

It is an arithmetic number, because the mean of its divisors is an integer number (5505072).

Almost surely, 2^21332123 is an apocalyptic number.

21332123 is a deficient number, since it is larger than the sum of its proper divisors (688165).

21332123 is an equidigital number, since it uses as much as digits as its factorization.

21332123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 688164.

The product of its digits is 216, while the sum is 17.

The square root of 21332123 is about 4618.6711292319. The cubic root of 21332123 is about 277.3392646519.

Adding to 21332123 its reverse (32123312), we get a palindrome (53455435).

The spelling of 21332123 in words is "twenty-one million, three hundred thirty-two thousand, one hundred twenty-three".