21204683 has 2 divisors, whose sum is σ = 21204684. Its totient is φ = 21204682.

The previous prime is 21204679. The next prime is 21204707. The reversal of 21204683 is 38640212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21204683 - 2² = 21204679 is a prime.

It is a super-3 number, since 3×21204683³ (a number of 23 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not a weakly prime, because it can be changed into another prime (21204583) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10602341 + 10602342.

It is an arithmetic number, because the mean of its divisors is an integer number (10602342).

Almost surely, 2^21204683 is an apocalyptic number.

21204683 is a deficient number, since it is larger than the sum of its proper divisors (1).

21204683 is an equidigital number, since it uses as much as digits as its factorization.

21204683 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2304, while the sum is 26.

The square root of 21204683 is about 4604.8542865111. The cubic root of 21204683 is about 276.7858780468.

Adding to 21204683 its reverse (38640212), we get a palindrome (59844895).

The spelling of 21204683 in words is "twenty-one million, two hundred four thousand, six hundred eighty-three".