21101111189 has 2 divisors, whose sum is σ = 21101111190. Its totient is φ = 21101111188.

The previous prime is 21101111173. The next prime is 21101111221. The reversal of 21101111189 is 98111110112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16055424100 + 5045687089 = 126710^2 + 71033^2 .

It is a cyclic number.

It is not a de Polignac number, because 21101111189 - 2⁴ = 21101111173 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21101111149) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10550555594 + 10550555595.

It is an arithmetic number, because the mean of its divisors is an integer number (10550555595).

Almost surely, 2^21101111189 is an apocalyptic number.

It is an amenable number.

21101111189 is a deficient number, since it is larger than the sum of its proper divisors (1).

21101111189 is an equidigital number, since it uses as much as digits as its factorization.

21101111189 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 144, while the sum is 26.

The spelling of 21101111189 in words is "twenty-one billion, one hundred one million, one hundred eleven thousand, one hundred eighty-nine".