21008752 has 20 divisors (see below), whose sum is σ = 42474960. Its totient is φ = 10047488.

The previous prime is 21008749. The next prime is 21008761. The reversal of 21008752 is 25780012.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 28177 + ... + 28912.

It is an arithmetic number, because the mean of its divisors is an integer number (2123748).

Almost surely, 2^21008752 is an apocalyptic number.

It is an amenable number.

21008752 is an abundant number, since it is smaller than the sum of its proper divisors (21466208).

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

21008752 is a wasteful number, since it uses less digits than its factorization.

21008752 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57120 (or 57114 counting only the distinct ones).

The product of its (nonzero) digits is 1120, while the sum is 25.

The square root of 21008752 is about 4583.5305169705. The cubic root of 21008752 is about 275.9307394647.

Adding to 21008752 its reverse (25780012), we get a palindrome (46788764).

The spelling of 21008752 in words is "twenty-one million, eight thousand, seven hundred fifty-two".