21100663349189 has 2 divisors, whose sum is σ = 21100663349190. Its totient is φ = 21100663349188.

The previous prime is 21100663349179. The next prime is 21100663349201. The reversal of 21100663349189 is 98194336600112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18848361760900 + 2252301588289 = 4341470^2 + 1500767^2 .

It is a cyclic number.

It is not a de Polignac number, because 21100663349189 - 2⁴ = 21100663349173 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21100663349189.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21100663349179) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10550331674594 + 10550331674595.

It is an arithmetic number, because the mean of its divisors is an integer number (10550331674595).

Almost surely, 2^{21100663349189} is an apocalyptic number.

It is an amenable number.

21100663349189 is a deficient number, since it is larger than the sum of its proper divisors (1).

21100663349189 is an equidigital number, since it uses as much as digits as its factorization.

21100663349189 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1679616, while the sum is 53.

The spelling of 21100663349189 in words is "twenty-one trillion, one hundred billion, six hundred sixty-three million, three hundred forty-nine thousand, one hundred eighty-nine".