21418852 has 72 divisors (see below), whose sum is σ = 48987456. Its totient is φ = 7978176.

The previous prime is 21418847. The next prime is 21418853. The reversal of 21418852 is 25881412.

It is not an unprimeable number, because it can be changed into a prime (21418853) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 131323 + ... + 131485.

Almost surely, 2^21418852 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 21418852, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24493728).

21418852 is an abundant number, since it is smaller than the sum of its proper divisors (27568604).

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

21418852 is a wasteful number, since it uses less digits than its factorization.

21418852 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 225 (or 204 counting only the distinct ones).

The product of its digits is 5120, while the sum is 31.

The square root of 21418852 is about 4628.0505615216. The cubic root of 21418852 is about 277.7146114623.

The spelling of 21418852 in words is "twenty-one million, four hundred eighteen thousand, eight hundred fifty-two".