21251152 has 40 divisors (see below), whose sum is σ = 44997120. Its totient is φ = 9663360.

The previous prime is 21251141. The next prime is 21251179. The reversal of 21251152 is 25115212.

It is a super-2 number, since 2×21251152² = 903222922654208, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14049 + ... + 15487.

It is an arithmetic number, because the mean of its divisors is an integer number (1124928).

Almost surely, 2^21251152 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 21251152, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22498560).

21251152 is an abundant number, since it is smaller than the sum of its proper divisors (23745968).

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

21251152 is a wasteful number, since it uses less digits than its factorization.

21251152 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1531 (or 1525 counting only the distinct ones).

The product of its digits is 200, while the sum is 19.

The square root of 21251152 is about 4609.8971788967. The cubic root of 21251152 is about 276.9879179914.

Adding to 21251152 its reverse (25115212), we get a palindrome (46366364).

The spelling of 21251152 in words is "twenty-one million, two hundred fifty-one thousand, one hundred fifty-two".