21322312 has 32 divisors (see below), whose sum is σ = 44064000. Its totient is φ = 9592000.

The previous prime is 21322307. The next prime is 21322319.

21322312 is nontrivially palindromic in base 10.

It is not an unprimeable number, because it can be changed into a prime (21322319) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7689 + ... + 10087.

It is an arithmetic number, because the mean of its divisors is an integer number (1377000).

Almost surely, 2^21322312 is an apocalyptic number.

21322312 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21322312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22032000).

21322312 is an abundant number, since it is smaller than the sum of its proper divisors (22741688).

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

21322312 is a wasteful number, since it uses less digits than its factorization.

21322312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2517 (or 2513 counting only the distinct ones).

The product of its digits is 144, while the sum is 16.

The square root of 21322312 is about 4617.6089050503. The cubic root of 21322312 is about 277.2967404773.

It can be divided in two parts, 2132 and 2312, that added together give a palindrome (4444).

The spelling of 21322312 in words is "twenty-one million, three hundred twenty-two thousand, three hundred twelve".