21143691543589 has 2 divisors, whose sum is σ = 21143691543590. Its totient is φ = 21143691543588.

The previous prime is 21143691543521. The next prime is 21143691543643. The reversal of 21143691543589 is 98534519634112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19993686244900 + 1150005298689 = 4471430^2 + 1072383^2 .

It is a cyclic number.

It is not a de Polignac number, because 21143691543589 - 2¹¹ = 21143691541541 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21143694543589) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10571845771794 + 10571845771795.

It is an arithmetic number, because the mean of its divisors is an integer number (10571845771795).

Almost surely, 2^{21143691543589} is an apocalyptic number.

It is an amenable number.

21143691543589 is a deficient number, since it is larger than the sum of its proper divisors (1).

21143691543589 is an equidigital number, since it uses as much as digits as its factorization.

21143691543589 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 27993600, while the sum is 61.

The spelling of 21143691543589 in words is "twenty-one trillion, one hundred forty-three billion, six hundred ninety-one million, five hundred forty-three thousand, five hundred eighty-nine".