201020191 has 2 divisors, whose sum is σ = 201020192. Its totient is φ = 201020190.

The previous prime is 201020159. The next prime is 201020201. The reversal of 201020191 is 191020102.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 201020191 - 2⁵ = 201020159 is a prime.

It is equal to p_11132332 and since 201020191 and 11132332 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (201020101) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 100510095 + 100510096.

It is an arithmetic number, because the mean of its divisors is an integer number (100510096).

Almost surely, 2^201020191 is an apocalyptic number.

201020191 is a deficient number, since it is larger than the sum of its proper divisors (1).

201020191 is an equidigital number, since it uses as much as digits as its factorization.

201020191 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 36, while the sum is 16.

The square root of 201020191 is about 14178.1589425426. The cubic root of 201020191 is about 585.7962138958.

Adding to 201020191 its reverse (191020102), we get a palindrome (392040293).

It can be divided in two parts, 2010 and 20191, that added together give a square (22201 = 149²).

The spelling of 201020191 in words is "two hundred one million, twenty thousand, one hundred ninety-one".