21663204233389 has 2 divisors, whose sum is σ = 21663204233390. Its totient is φ = 21663204233388.

The previous prime is 21663204233347. The next prime is 21663204233471. The reversal of 21663204233389 is 98333240236612.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15237765059364 + 6425439174025 = 3903558^2 + 2534845^2 .

It is a cyclic number.

It is not a de Polignac number, because 21663204233389 - 2¹⁷ = 21663204102317 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21663204233789) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10831602116694 + 10831602116695.

It is an arithmetic number, because the mean of its divisors is an integer number (10831602116695).

Almost surely, 2^{21663204233389} is an apocalyptic number.

It is an amenable number.

21663204233389 is a deficient number, since it is larger than the sum of its proper divisors (1).

21663204233389 is an equidigital number, since it uses as much as digits as its factorization.

21663204233389 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6718464, while the sum is 52.

The spelling of 21663204233389 in words is "twenty-one trillion, six hundred sixty-three billion, two hundred four million, two hundred thirty-three thousand, three hundred eighty-nine".