21063312 has 30 divisors (see below), whose sum is σ = 58948422. Its totient is φ = 7021056.

The previous prime is 21063311. The next prime is 21063373. The reversal of 21063312 is 21336012.

21063312 is a `hidden beast` number, since 21 + 0 + 633 + 12 = 666.

It can be written as a sum of positive squares in only one way, i.e., 12278016 + 8785296 = 3504^2 + 2964^2 .

It is a super-2 number, since 2×21063312² = 887326224818688, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (21063311) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 72993 + ... + 73280.

Almost surely, 2^21063312 is an apocalyptic number.

It is an amenable number.

21063312 is an abundant number, since it is smaller than the sum of its proper divisors (37885110).

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

21063312 is a wasteful number, since it uses less digits than its factorization.

21063312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 146287 (or 146278 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 18.

The square root of 21063312 is about 4589.4784017359. The cubic root of 21063312 is about 276.1693982140.

Adding to 21063312 its reverse (21336012), we get a palindrome (42399324).

The spelling of 21063312 in words is "twenty-one million, sixty-three thousand, three hundred twelve".