201891243 has 16 divisors (see below), whose sum is σ = 279655200. Its totient is φ = 129400320.

The previous prime is 201891229. The next prime is 201891247. The reversal of 201891243 is 342198102.

It is not a de Polignac number, because 201891243 - 2⁵ = 201891211 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 201891243.

It is not an unprimeable number, because it can be changed into a prime (201891247) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16153 + ... + 25781.

It is an arithmetic number, because the mean of its divisors is an integer number (17478450).

Almost surely, 2^201891243 is an apocalyptic number.

201891243 is a deficient number, since it is larger than the sum of its proper divisors (77763957).

201891243 is a wasteful number, since it uses less digits than its factorization.

201891243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9902.

The product of its (nonzero) digits is 3456, while the sum is 30.

The square root of 201891243 is about 14208.8438305163. The cubic root of 201891243 is about 586.6411103207.

The spelling of 201891243 in words is "two hundred one million, eight hundred ninety-one thousand, two hundred forty-three".