21234512 has 30 divisors (see below), whose sum is σ = 44555742. Its totient is φ = 9799296.

The previous prime is 21234509. The next prime is 21234523. The reversal of 21234512 is 21543212.

It can be written as a sum of positive squares in 3 ways, for example, as 2085136 + 19149376 = 1444^2 + 4376^2 .

It is a congruent number.

It is an unprimeable number.

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 5 ways as a sum of consecutive naturals, for example, 1223 + ... + 6630.

Almost surely, 2^21234512 is an apocalyptic number.

It is an amenable number.

21234512 is an abundant number, since it is smaller than the sum of its proper divisors (23321230).

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

21234512 is a wasteful number, since it uses less digits than its factorization.

21234512 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7887 (or 7868 counting only the distinct ones).

The product of its digits is 480, while the sum is 20.

The square root of 21234512 is about 4608.0920129702. The cubic root of 21234512 is about 276.9156037553.

Adding to 21234512 its reverse (21543212), we get a palindrome (42777724).

The spelling of 21234512 in words is "twenty-one million, two hundred thirty-four thousand, five hundred twelve".