21827408 has 10 divisors (see below), whose sum is σ = 42290634. Its totient is φ = 10913696.

The previous prime is 21827389. The next prime is 21827453. The reversal of 21827408 is 80472812.

It can be written as a sum of positive squares in only one way, i.e., 20720704 + 1106704 = 4552^2 + 1052^2 .

It is a congruent number.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 682091 + ... + 682122.

Almost surely, 2^21827408 is an apocalyptic number.

It is an amenable number.

21827408 is a deficient number, since it is larger than the sum of its proper divisors (20463226).

21827408 is a wasteful number, since it uses less digits than its factorization.

21827408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1364221 (or 1364215 counting only the distinct ones).

The product of its (nonzero) digits is 7168, while the sum is 32.

The square root of 21827408 is about 4671.9811643456. The cubic root of 21827408 is about 279.4692667524.

The spelling of 21827408 in words is "twenty-one million, eight hundred twenty-seven thousand, four hundred eight".