21544212 has 24 divisors (see below), whose sum is σ = 51629536. Its totient is φ = 6987168.

The previous prime is 21544207. The next prime is 21544213. The reversal of 21544212 is 21244512.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21544213) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 23818 + ... + 24705.

Almost surely, 2^21544212 is an apocalyptic number.

It is an amenable number.

21544212 is an abundant number, since it is smaller than the sum of its proper divisors (30085324).

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

21544212 is a wasteful number, since it uses less digits than its factorization.

21544212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48567 (or 48565 counting only the distinct ones).

The product of its digits is 640, while the sum is 21.

The square root of 21544212 is about 4641.5743018937. The cubic root of 21544212 is about 278.2553594513.

Adding to 21544212 its reverse (21244512), we get a palindrome (42788724).

The spelling of 21544212 in words is "twenty-one million, five hundred forty-four thousand, two hundred twelve".