201009191 has 2 divisors, whose sum is σ = 201009192. Its totient is φ = 201009190.

The previous prime is 201009163. The next prime is 201009199. The reversal of 201009191 is 191900102.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 201009191 - 2¹⁸ = 200747047 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (201009199) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 100504595 + 100504596.

It is an arithmetic number, because the mean of its divisors is an integer number (100504596).

Almost surely, 2^201009191 is an apocalyptic number.

201009191 is a deficient number, since it is larger than the sum of its proper divisors (1).

201009191 is an equidigital number, since it uses as much as digits as its factorization.

201009191 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 162, while the sum is 23.

The square root of 201009191 is about 14177.7710166302. The cubic root of 201009191 is about 585.7855286078.

Adding to 201009191 its reverse (191900102), we get a palindrome (392909293).

The spelling of 201009191 in words is "two hundred one million, nine thousand, one hundred ninety-one".