21036448 has 48 divisors (see below), whose sum is σ = 43110144. Its totient is φ = 10097920.

The previous prime is 21036443. The next prime is 21036451. The reversal of 21036448 is 84463012.

It is a super-3 number, since 3×21036448³ (a number of 23 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21036443) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 106686 + ... + 106882.

It is an arithmetic number, because the mean of its divisors is an integer number (898128).

Almost surely, 2^21036448 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 21036448, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21555072).

21036448 is an abundant number, since it is smaller than the sum of its proper divisors (22073696).

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

21036448 is a wasteful number, since it uses less digits than its factorization.

21036448 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 325 (or 317 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 28.

The square root of 21036448 is about 4586.5507737296. The cubic root of 21036448 is about 276.0519400953.

The spelling of 21036448 in words is "twenty-one million, thirty-six thousand, four hundred forty-eight".