21043234 has 16 divisors (see below), whose sum is σ = 32772096. Its totient is φ = 10123200.

The previous prime is 21043223. The next prime is 21043237. The reversal of 21043234 is 43234012.

It is not an unprimeable number, because it can be changed into a prime (21043237) 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 7 ways as a sum of consecutive naturals, for example, 10954 + ... + 12730.

It is an arithmetic number, because the mean of its divisors is an integer number (2048256).

Almost surely, 2^21043234 is an apocalyptic number.

21043234 is a deficient number, since it is larger than the sum of its proper divisors (11728862).

21043234 is a wasteful number, since it uses less digits than its factorization.

21043234 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2001.

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

The square root of 21043234 is about 4587.2904856789. The cubic root of 21043234 is about 276.0816201229.

Adding to 21043234 its reverse (43234012), we get a palindrome (64277246).

The spelling of 21043234 in words is "twenty-one million, forty-three thousand, two hundred thirty-four".