21340233 has 8 divisors (see below), whose sum is σ = 31615200. Its totient is φ = 14226804.

The previous prime is 21340223. The next prime is 21340243. The reversal of 21340233 is 33204312.

It is an interprime number because it is at equal distance from previous prime (21340223) and next prime (21340243).

It is not a de Polignac number, because 21340233 - 2⁴ = 21340217 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21340223) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 395163 + ... + 395216.

It is an arithmetic number, because the mean of its divisors is an integer number (3951900).

Almost surely, 2^21340233 is an apocalyptic number.

It is an amenable number.

21340233 is a deficient number, since it is larger than the sum of its proper divisors (10274967).

21340233 is an equidigital number, since it uses as much as digits as its factorization.

21340233 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 790388 (or 790382 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 18.

The square root of 21340233 is about 4619.5490039613. The cubic root of 21340233 is about 277.3744062779.

Adding to 21340233 its reverse (33204312), we get a palindrome (54544545).

The spelling of 21340233 in words is "twenty-one million, three hundred forty thousand, two hundred thirty-three".