21243234 has 24 divisors (see below), whose sum is σ = 45136368. Its totient is φ = 6664000.

The previous prime is 21243227. The next prime is 21243253. The reversal of 21243234 is 43234212.

It is a self number, because there is not a number n which added to its sum of digits gives 21243234.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4392 + ... + 7859.

It is an arithmetic number, because the mean of its divisors is an integer number (1880682).

Almost surely, 2^21243234 is an apocalyptic number.

21243234 is an abundant number, since it is smaller than the sum of its proper divisors (23893134).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21243234 is a wasteful number, since it uses less digits than its factorization.

21243234 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12290 (or 12273 counting only the distinct ones).

The product of its digits is 1152, while the sum is 21.

The square root of 21243234 is about 4609.0382944818. The cubic root of 21243234 is about 276.9535125973.

Adding to 21243234 its reverse (43234212), we get a palindrome (64477446).

The spelling of 21243234 in words is "twenty-one million, two hundred forty-three thousand, two hundred thirty-four".