21234576 has 80 divisors (see below), whose sum is σ = 60496128. Its totient is φ = 6364800.

The previous prime is 21234541. The next prime is 21234593. The reversal of 21234576 is 67543212.

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 15 ways as a sum of consecutive naturals, for example, 69015 + ... + 69321.

Almost surely, 2^21234576 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21234576, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30248064).

21234576 is an abundant number, since it is smaller than the sum of its proper divisors (39261552).

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

21234576 is a wasteful number, since it uses less digits than its factorization.

21234576 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 460 (or 454 counting only the distinct ones).

The product of its digits is 10080, while the sum is 30.

The square root of 21234576 is about 4608.0989572708. The cubic root of 21234576 is about 276.9158819593.

Adding to 21234576 its reverse (67543212), we get a palindrome (88777788).

The spelling of 21234576 in words is "twenty-one million, two hundred thirty-four thousand, five hundred seventy-six".