21248552 has 32 divisors (see below), whose sum is σ = 43190280. Its totient is φ = 9742080.

The previous prime is 21248543. The next prime is 21248567. The reversal of 21248552 is 25584212.

It can be written as a sum of positive squares in 4 ways, for example, as 21031396 + 217156 = 4586^2 + 466^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17402 + ... + 18582.

Almost surely, 2^21248552 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 21248552, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21595140).

21248552 is an abundant number, since it is smaller than the sum of its proper divisors (21941728).

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

21248552 is a wasteful number, since it uses less digits than its factorization.

21248552 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1373 (or 1369 counting only the distinct ones).

The product of its digits is 6400, while the sum is 29.

The square root of 21248552 is about 4609.6151683194. The cubic root of 21248552 is about 276.9766213810.

The spelling of 21248552 in words is "twenty-one million, two hundred forty-eight thousand, five hundred fifty-two".