21316412 has 24 divisors (see below), whose sum is σ = 40689600. Its totient is φ = 9711936.

The previous prime is 21316397. The next prime is 21316417. The reversal of 21316412 is 21461312.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21316417) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1514 + ... + 6702.

It is an arithmetic number, because the mean of its divisors is an integer number (1695400).

Almost surely, 2^21316412 is an apocalyptic number.

It is an amenable number.

21316412 is a deficient number, since it is larger than the sum of its proper divisors (19373188).

21316412 is a wasteful number, since it uses less digits than its factorization.

21316412 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5285 (or 5283 counting only the distinct ones).

The product of its digits is 288, while the sum is 20.

The square root of 21316412 is about 4616.9700020685. The cubic root of 21316412 is about 277.2711616111.

Adding to 21316412 its reverse (21461312), we get a palindrome (42777724).

The spelling of 21316412 in words is "twenty-one million, three hundred sixteen thousand, four hundred twelve".