21323379 has 24 divisors (see below), whose sum is σ = 36082368. Its totient is φ = 11076240.

The previous prime is 21323371. The next prime is 21323417. The reversal of 21323379 is 97332312.

It is not a de Polignac number, because 21323379 - 2³ = 21323371 is a prime.

It is a plaindrome in base 13.

It is not an unprimeable number, because it can be changed into a prime (21323371) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4977 + ... + 8210.

It is an arithmetic number, because the mean of its divisors is an integer number (1503432).

Almost surely, 2^21323379 is an apocalyptic number.

21323379 is a deficient number, since it is larger than the sum of its proper divisors (14758989).

21323379 is a wasteful number, since it uses less digits than its factorization.

21323379 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13215 (or 13208 counting only the distinct ones).

The product of its digits is 6804, while the sum is 30.

The square root of 21323379 is about 4617.7244395914. The cubic root of 21323379 is about 277.3013658463.

It can be divided in two parts, 213233 and 79, that added together give a palindrome (213312).

The spelling of 21323379 in words is "twenty-one million, three hundred twenty-three thousand, three hundred seventy-nine".