201800894389891 has 2 divisors, whose sum is σ = 201800894389892. Its totient is φ = 201800894389890.

The previous prime is 201800894389883. The next prime is 201800894389961. The reversal of 201800894389891 is 198983498008102.

It is an a-pointer prime, because the next prime (201800894389961) can be obtained adding 201800894389891 to its sum of digits (70).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 201800894389891 - 2³ = 201800894389883 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 201800894389891.

It is not a weakly prime, because it can be changed into another prime (201800894389841) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 100900447194945 + 100900447194946.

It is an arithmetic number, because the mean of its divisors is an integer number (100900447194946).

Almost surely, 2^{201800894389891} is an apocalyptic number.

201800894389891 is a deficient number, since it is larger than the sum of its proper divisors (1).

201800894389891 is an equidigital number, since it uses as much as digits as its factorization.

201800894389891 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 71663616, while the sum is 70.

The spelling of 201800894389891 in words is "two hundred one trillion, eight hundred billion, eight hundred ninety-four million, three hundred eighty-nine thousand, eight hundred ninety-one".