21324212 has 36 divisors (see below), whose sum is σ = 46754820. Its totient is φ = 8434944.

The previous prime is 21324203. The next prime is 21324221. The reversal of 21324212 is 21242312.

It is an interprime number because it is at equal distance from previous prime (21324203) and next prime (21324221).

It can be written as a sum of positive squares in 2 ways, for example, as 8976016 + 12348196 = 2996^2 + 3514^2 .

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1637 + ... + 6732.

It is an arithmetic number, because the mean of its divisors is an integer number (1298745).

Almost surely, 2^21324212 is an apocalyptic number.

It is an amenable number.

21324212 is an abundant number, since it is smaller than the sum of its proper divisors (25430608).

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

21324212 is a wasteful number, since it uses less digits than its factorization.

21324212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8400 (or 8391 counting only the distinct ones).

The product of its digits is 192, while the sum is 17.

The square root of 21324212 is about 4617.8146346513. The cubic root of 21324212 is about 277.3049767348.

Adding to 21324212 its reverse (21242312), we get a palindrome (42566524).

The spelling of 21324212 in words is "twenty-one million, three hundred twenty-four thousand, two hundred twelve".