21244752 has 120 divisors (see below), whose sum is σ = 62984064. Its totient is φ = 6676992.

The previous prime is 21244723. The next prime is 21244757. The reversal of 21244752 is 25744212.

21244752 is a `hidden beast` number, since 212 + 447 + 5 + 2 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21244757) 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, 290988 + ... + 291060.

Almost surely, 2^21244752 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 21244752, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31492032).

21244752 is an abundant number, since it is smaller than the sum of its proper divisors (41739312).

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

21244752 is a wasteful number, since it uses less digits than its factorization.

21244752 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 177 (or 168 counting only the distinct ones).

The product of its digits is 4480, while the sum is 27.

The square root of 21244752 is about 4609.2029679761. The cubic root of 21244752 is about 276.9601092925.

Adding to 21244752 its reverse (25744212), we get a palindrome (46988964).

The spelling of 21244752 in words is "twenty-one million, two hundred forty-four thousand, seven hundred fifty-two".