21043687333 has 2 divisors, whose sum is σ = 21043687334. Its totient is φ = 21043687332.

The previous prime is 21043687319. The next prime is 21043687387. The reversal of 21043687333 is 33378634012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17993003044 + 3050684289 = 134138^2 + 55233^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21043687333 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21043627333) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10521843666 + 10521843667.

It is an arithmetic number, because the mean of its divisors is an integer number (10521843667).

Almost surely, 2^21043687333 is an apocalyptic number.

It is an amenable number.

21043687333 is a deficient number, since it is larger than the sum of its proper divisors (1).

21043687333 is an equidigital number, since it uses as much as digits as its factorization.

21043687333 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 217728, while the sum is 40.

The spelling of 21043687333 in words is "twenty-one billion, forty-three million, six hundred eighty-seven thousand, three hundred thirty-three".