21324812 has 6 divisors (see below), whose sum is σ = 37318428. Its totient is φ = 10662404.

The previous prime is 21324803. The next prime is 21324847. The reversal of 21324812 is 21842312.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2665598 + ... + 2665605.

It is an arithmetic number, because the mean of its divisors is an integer number (6219738).

Almost surely, 2^21324812 is an apocalyptic number.

It is an amenable number.

21324812 is a deficient number, since it is larger than the sum of its proper divisors (15993616).

21324812 is a wasteful number, since it uses less digits than its factorization.

21324812 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5331207 (or 5331205 counting only the distinct ones).

The product of its digits is 768, while the sum is 23.

The square root of 21324812 is about 4617.8795999896. The cubic root of 21324812 is about 277.3075775566.

The spelling of 21324812 in words is "twenty-one million, three hundred twenty-four thousand, eight hundred twelve".