21235233 has 16 divisors (see below), whose sum is σ = 29690496. Its totient is φ = 13474560.

The previous prime is 21235223. The next prime is 21235243. The reversal of 21235233 is 33253212.

It is an interprime number because it is at equal distance from previous prime (21235223) and next prime (21235243).

It is not a de Polignac number, because 21235233 - 2¹⁰ = 21234209 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21235213) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15991 + ... + 17267.

It is an arithmetic number, because the mean of its divisors is an integer number (1855656).

Almost surely, 2^21235233 is an apocalyptic number.

21235233 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

It is an amenable number.

21235233 is a deficient number, since it is larger than the sum of its proper divisors (8455263).

21235233 is a wasteful number, since it uses less digits than its factorization.

21235233 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1544.

The product of its digits is 1080, while the sum is 21.

The square root of 21235233 is about 4608.1702442510. The cubic root of 21235233 is about 276.9187378653.

Adding to 21235233 its reverse (33253212), we get a palindrome (54488445).

The spelling of 21235233 in words is "twenty-one million, two hundred thirty-five thousand, two hundred thirty-three".