21283712 has 32 divisors (see below), whose sum is σ = 42631920. Its totient is φ = 10584064.

The previous prime is 21283699. The next prime is 21283721. The reversal of 21283712 is 21738212.

It is a tau number, because it is divible by the number of its divisors (32).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32573 + ... + 33219.

Almost surely, 2^21283712 is an apocalyptic number.

It is an amenable number.

21283712 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

21283712 is an equidigital number, since it uses as much as digits as its factorization.

21283712 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 918 (or 906 counting only the distinct ones).

The product of its digits is 1344, while the sum is 26.

The square root of 21283712 is about 4613.4273593501. The cubic root of 21283712 is about 277.1293083579.

The spelling of 21283712 in words is "twenty-one million, two hundred eighty-three thousand, seven hundred twelve".