21412636 has 48 divisors (see below), whose sum is σ = 44706816. Its totient is φ = 8783424.

The previous prime is 21412631. The next prime is 21412649. The reversal of 21412636 is 63621412.

It is a self number, because there is not a number n which added to its sum of digits gives 21412636.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21412631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 69595 + ... + 69901.

It is an arithmetic number, because the mean of its divisors is an integer number (931392).

Almost surely, 2^21412636 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 21412636, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22353408).

21412636 is an abundant number, since it is smaller than the sum of its proper divisors (23294180).

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

21412636 is a wasteful number, since it uses less digits than its factorization.

21412636 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 418 (or 416 counting only the distinct ones).

The product of its digits is 1728, while the sum is 25.

The square root of 21412636 is about 4627.3789557373. The cubic root of 21412636 is about 277.6877435261.

The spelling of 21412636 in words is "twenty-one million, four hundred twelve thousand, six hundred thirty-six".