21316410 has 48 divisors (see below), whose sum is σ = 55710720. Its totient is φ = 5654880.

The previous prime is 21316397. The next prime is 21316417. The reversal of 21316410 is 1461312.

It is a happy number.

21316410 is a `hidden beast` number, since 21 + 3 + 1 + 641 + 0 = 666.

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 (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 23 ways as a sum of consecutive naturals, for example, 21015 + ... + 22005.

It is an arithmetic number, because the mean of its divisors is an integer number (1160640).

Almost surely, 2^21316410 is an apocalyptic number.

21316410 is an abundant number, since it is smaller than the sum of its proper divisors (34394310).

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

21316410 is a wasteful number, since it uses less digits than its factorization.

21316410 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1243 (or 1240 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

The square root of 21316410 is about 4616.9697854762. The cubic root of 21316410 is about 277.2711529395.

Adding to 21316410 its reverse (1461312), we get a palindrome (22777722).

The spelling of 21316410 in words is "twenty-one million, three hundred sixteen thousand, four hundred ten".