21312033 has 8 divisors (see below), whose sum is σ = 30087648. Its totient is φ = 13372224.

The previous prime is 21312023. The next prime is 21312059. The reversal of 21312033 is 33021312.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21312033 - 2⁴ = 21312017 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21312023) 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, 208891 + ... + 208992.

It is an arithmetic number, because the mean of its divisors is an integer number (3760956).

Almost surely, 2^21312033 is an apocalyptic number.

It is an amenable number.

21312033 is a deficient number, since it is larger than the sum of its proper divisors (8775615).

21312033 is a wasteful number, since it uses less digits than its factorization.

21312033 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 417903.

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

The square root of 21312033 is about 4616.4957489420. The cubic root of 21312033 is about 277.2521738383.

Adding to 21312033 its reverse (33021312), we get a palindrome (54333345).

It can be divided in two parts, 213 and 12033, that added together give a triangular number (12246 = T₁₅₆).

The spelling of 21312033 in words is "twenty-one million, three hundred twelve thousand, thirty-three".