21233031 has 4 divisors (see below), whose sum is σ = 28310712. Its totient is φ = 14155352.

The previous prime is 21233029. The next prime is 21233059. The reversal of 21233031 is 13033212.

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 21233031 - 2¹ = 21233029 is a prime.

It is a super-2 number, since 2×21233031² = 901683210893922, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21233031.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21233011) 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, 3538836 + ... + 3538841.

It is an arithmetic number, because the mean of its divisors is an integer number (7077678).

Almost surely, 2^21233031 is an apocalyptic number.

21233031 is a deficient number, since it is larger than the sum of its proper divisors (7077681).

21233031 is an equidigital number, since it uses as much as digits as its factorization.

21233031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7077680.

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

The square root of 21233031 is about 4607.9313145923. The cubic root of 21233031 is about 276.9091657839.

Adding to 21233031 its reverse (13033212), we get a palindrome (34266243).

The spelling of 21233031 in words is "twenty-one million, two hundred thirty-three thousand, thirty-one".