21030323 has 4 divisors (see below), whose sum is σ = 21039648. Its totient is φ = 21021000.

The previous prime is 21030313. The next prime is 21030329. The reversal of 21030323 is 32303012.

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 is a cyclic number.

It is not a de Polignac number, because 21030323 - 2¹⁸ = 20768179 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21030298 and 21030307.

It is not an unprimeable number, because it can be changed into a prime (21030329) 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, 1073 + ... + 6573.

It is an arithmetic number, because the mean of its divisors is an integer number (5259912).

Almost surely, 2^21030323 is an apocalyptic number.

21030323 is a deficient number, since it is larger than the sum of its proper divisors (9325).

21030323 is an equidigital number, since it uses as much as digits as its factorization.

21030323 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9324.

The product of its (nonzero) digits is 108, while the sum is 14.

The square root of 21030323 is about 4585.8830120272. The cubic root of 21030323 is about 276.0251456121.

Adding to 21030323 its reverse (32303012), we get a palindrome (53333335).

The spelling of 21030323 in words is "twenty-one million, thirty thousand, three hundred twenty-three".