21344023 has 4 divisors (see below), whose sum is σ = 22272048. Its totient is φ = 20416000.

The previous prime is 21344021. The next prime is 21344033. The reversal of 21344023 is 32044312.

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 21344023 - 2¹ = 21344021 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21344021) 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, 463978 + ... + 464023.

It is an arithmetic number, because the mean of its divisors is an integer number (5568012).

Almost surely, 2^21344023 is an apocalyptic number.

21344023 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

21344023 is a deficient number, since it is larger than the sum of its proper divisors (928025).

21344023 is an equidigital number, since it uses as much as digits as its factorization.

21344023 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 928024.

The product of its (nonzero) digits is 576, while the sum is 19.

The square root of 21344023 is about 4619.9591989540. The cubic root of 21344023 is about 277.3908257608.

Adding to 21344023 its reverse (32044312), we get a palindrome (53388335).

The spelling of 21344023 in words is "twenty-one million, three hundred forty-four thousand, twenty-three".