21126648 has 64 divisors (see below), whose sum is σ = 57036960. Its totient is φ = 6496256.

The previous prime is 21126643. The next prime is 21126649. The reversal of 21126648 is 84662112.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21126643) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 21136 + ... + 22112.

Almost surely, 2^21126648 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 21126648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28518480).

21126648 is an abundant number, since it is smaller than the sum of its proper divisors (35910312).

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

21126648 is a wasteful number, since it uses less digits than its factorization.

21126648 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1056 (or 1052 counting only the distinct ones).

The product of its digits is 4608, while the sum is 30.

The square root of 21126648 is about 4596.3733529817. The cubic root of 21126648 is about 276.4459289948.

The spelling of 21126648 in words is "twenty-one million, one hundred twenty-six thousand, six hundred forty-eight".