21086336 has 32 divisors (see below), whose sum is σ = 42237180. Its totient is φ = 10485760.

The previous prime is 21086327. The next prime is 21086347. The reversal of 21086336 is 63368012.

It can be written as a sum of positive squares in 2 ways, for example, as 15054400 + 6031936 = 3880^2 + 2456^2 .

It is a tau number, because it is divible by the number of its divisors (32).

It is a junction number, because it is equal to n+sod(n) for n = 21086299 and 21086308.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32576 + ... + 33216.

Almost surely, 2^21086336 is an apocalyptic number.

It is an amenable number.

21086336 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

21086336 is an equidigital number, since it uses as much as digits as its factorization.

21086336 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 912 (or 900 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 29.

The square root of 21086336 is about 4591.9860626966. The cubic root of 21086336 is about 276.2699871563.

The spelling of 21086336 in words is "twenty-one million, eighty-six thousand, three hundred thirty-six".