21130323 has 4 divisors (see below), whose sum is σ = 28173768. Its totient is φ = 14086880.

The previous prime is 21130321. The next prime is 21130331. The reversal of 21130323 is 32303112.

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 21130323 - 2¹ = 21130321 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21130321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3521718 + ... + 3521723.

It is an arithmetic number, because the mean of its divisors is an integer number (7043442).

Almost surely, 2^21130323 is an apocalyptic number.

21130323 is a deficient number, since it is larger than the sum of its proper divisors (7043445).

21130323 is an equidigital number, since it uses as much as digits as its factorization.

21130323 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7043444.

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

The square root of 21130323 is about 4596.7731073004. The cubic root of 21130323 is about 276.4619574073.

Adding to 21130323 its reverse (32303112), we get a palindrome (53433435).

The spelling of 21130323 in words is "twenty-one million, one hundred thirty thousand, three hundred twenty-three".