21440448 has 42 divisors (see below), whose sum is σ = 61456824. Its totient is φ = 7146624.

The previous prime is 21440431. The next prime is 21440449. The reversal of 21440448 is 84404412.

It is a happy number.

21440448 is a `hidden beast` number, since 214 + 4 + 0 + 448 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21440449) 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 5 ways as a sum of consecutive naturals, for example, 18036 + ... + 19187.

Almost surely, 2^21440448 is an apocalyptic number.

It is an amenable number.

21440448 is an abundant number, since it is smaller than the sum of its proper divisors (40016376).

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

21440448 is a wasteful number, since it uses less digits than its factorization.

21440448 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37241 (or 37228 counting only the distinct ones).

The product of its (nonzero) digits is 4096, while the sum is 27.

The square root of 21440448 is about 4630.3831374952. The cubic root of 21440448 is about 277.8079172749.

The spelling of 21440448 in words is "twenty-one million, four hundred forty thousand, four hundred forty-eight".