198591311 has 2 divisors, whose sum is σ = 198591312. Its totient is φ = 198591310.

The previous prime is 198591293. The next prime is 198591347. The reversal of 198591311 is 113195891.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 198591311 - 2²⁶ = 131482447 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (198591011) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99295655 + 99295656.

It is an arithmetic number, because the mean of its divisors is an integer number (99295656).

Almost surely, 2^198591311 is an apocalyptic number.

198591311 is a deficient number, since it is larger than the sum of its proper divisors (1).

198591311 is an equidigital number, since it uses as much as digits as its factorization.

198591311 is an evil number, because the sum of its binary digits is even.

The product of its digits is 9720, while the sum is 38.

The square root of 198591311 is about 14092.2429371623. The cubic root of 198591311 is about 583.4273008532.

The spelling of 198591311 in words is "one hundred ninety-eight million, five hundred ninety-one thousand, three hundred eleven".