21382312 has 64 divisors (see below), whose sum is σ = 48153600. Its totient is φ = 8709120.

The previous prime is 21382307. The next prime is 21382327. The reversal of 21382312 is 21328312.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 189168 + ... + 189280.

It is an arithmetic number, because the mean of its divisors is an integer number (752400).

Almost surely, 2^21382312 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21382312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24076800).

21382312 is an abundant number, since it is smaller than the sum of its proper divisors (26771288).

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

21382312 is a wasteful number, since it uses less digits than its factorization.

21382312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 266 (or 262 counting only the distinct ones).

The product of its digits is 576, while the sum is 22.

The square root of 21382312 is about 4624.1012099650. The cubic root of 21382312 is about 277.5565969565.

The spelling of 21382312 in words is "twenty-one million, three hundred eighty-two thousand, three hundred twelve".