991898000201 has 2 divisors, whose sum is σ = 991898000202. Its totient is φ = 991898000200.

The previous prime is 991898000131. The next prime is 991898000209. The reversal of 991898000201 is 102000898199.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 924636096400 + 67261903801 = 961580^2 + 259349^2 .

It is a cyclic number.

It is not a de Polignac number, because 991898000201 - 2²² = 991893805897 is a prime.

It is not a weakly prime, because it can be changed into another prime (991898000209) 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, 495949000100 + 495949000101.

It is an arithmetic number, because the mean of its divisors is an integer number (495949000101).

Almost surely, 2^991898000201 is an apocalyptic number.

It is an amenable number.

991898000201 is a deficient number, since it is larger than the sum of its proper divisors (1).

991898000201 is an equidigital number, since it uses as much as digits as its factorization.

991898000201 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 93312, while the sum is 47.

The spelling of 991898000201 in words is "nine hundred ninety-one billion, eight hundred ninety-eight million, two hundred one", and thus it is an aban number.