21560252 has 48 divisors (see below), whose sum is σ = 45373440. Its totient is φ = 8769600.

The previous prime is 21560251. The next prime is 21560291. The reversal of 21560252 is 25206512.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21560251) 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, 51002 + ... + 51422.

It is an arithmetic number, because the mean of its divisors is an integer number (945280).

Almost surely, 2^21560252 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 21560252, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22686720).

21560252 is an abundant number, since it is smaller than the sum of its proper divisors (23813188).

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

21560252 is a wasteful number, since it uses less digits than its factorization.

21560252 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 522 (or 520 counting only the distinct ones).

The product of its (nonzero) digits is 1200, while the sum is 23.

The square root of 21560252 is about 4643.3018424393. The cubic root of 21560252 is about 278.3243974645.

Adding to 21560252 its reverse (25206512), we get a palindrome (46766764).

It can be divided in two parts, 21560 and 252, that added together give a palindrome (21812).

The spelling of 21560252 in words is "twenty-one million, five hundred sixty thousand, two hundred fifty-two".