21012448 has 24 divisors (see below), whose sum is σ = 42488712. Its totient is φ = 10221696.

The previous prime is 21012421. The next prime is 21012449. The reversal of 21012448 is 84421012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21012449) 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 3 ways as a sum of consecutive naturals, for example, 7690 + ... + 10057.

It is an arithmetic number, because the mean of its divisors is an integer number (1770363).

Almost surely, 2^21012448 is an apocalyptic number.

It is an amenable number.

21012448 is an abundant number, since it is smaller than the sum of its proper divisors (21476264).

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

21012448 is a wasteful number, since it uses less digits than its factorization.

21012448 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17794 (or 17786 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 22.

The square root of 21012448 is about 4583.9336818938. The cubic root of 21012448 is about 275.9469197089.

The spelling of 21012448 in words is "twenty-one million, twelve thousand, four hundred forty-eight".