21443008 has 14 divisors (see below), whose sum is σ = 42551096. Its totient is φ = 10721472.

The previous prime is 21443003. The next prime is 21443033. The reversal of 21443008 is 80034412.

It is a self number, because there is not a number n which added to its sum of digits gives 21443008.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21443003) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 167460 + ... + 167587.

It is an arithmetic number, because the mean of its divisors is an integer number (3039364).

Almost surely, 2^21443008 is an apocalyptic number.

It is an amenable number.

21443008 is a deficient number, since it is larger than the sum of its proper divisors (21108088).

21443008 is an equidigital number, since it uses as much as digits as its factorization.

21443008 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 335059 (or 335049 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 22.

The square root of 21443008 is about 4630.6595642522. The cubic root of 21443008 is about 277.8189736353.

The spelling of 21443008 in words is "twenty-one million, four hundred forty-three thousand, eight".