21304752 has 80 divisors (see below), whose sum is σ = 63448320. Its totient is φ = 6034176.

The previous prime is 21304747. The next prime is 21304753. The reversal of 21304752 is 25740312.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is not an unprimeable number, because it can be changed into a prime (21304753) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 54574 + ... + 54962.

It is an arithmetic number, because the mean of its divisors is an integer number (793104).

Almost surely, 2^21304752 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 21304752, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31724160).

21304752 is an abundant number, since it is smaller than the sum of its proper divisors (42143568).

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

21304752 is a wasteful number, since it uses less digits than its factorization.

21304752 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 570 (or 564 counting only the distinct ones).

The product of its (nonzero) digits is 1680, while the sum is 24.

The square root of 21304752 is about 4615.7070964263. The cubic root of 21304752 is about 277.2205969507.

The spelling of 21304752 in words is "twenty-one million, three hundred four thousand, seven hundred fifty-two".