21463312 has 40 divisors (see below), whose sum is σ = 47149760. Its totient is φ = 9383040.

The previous prime is 21463289. The next prime is 21463327. The reversal of 21463312 is 21336412.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1237 + ... + 6667.

It is an arithmetic number, because the mean of its divisors is an integer number (1178744).

Almost surely, 2^21463312 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 21463312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23574880).

21463312 is an abundant number, since it is smaller than the sum of its proper divisors (25686448).

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

21463312 is a wasteful number, since it uses less digits than its factorization.

21463312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5471 (or 5465 counting only the distinct ones).

The product of its digits is 864, while the sum is 22.

The square root of 21463312 is about 4632.8513898030. The cubic root of 21463312 is about 277.9066332425.

Adding to 21463312 its reverse (21336412), we get a palindrome (42799724).

The spelling of 21463312 in words is "twenty-one million, four hundred sixty-three thousand, three hundred twelve".