2001000191 has 4 divisors (see below), whose sum is σ = 2002073832. Its totient is φ = 1999926552.

The previous prime is 2001000151. The next prime is 2001000223. The reversal of 2001000191 is 1910001002.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 2001000191 - 2¹⁰ = 2000999167 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2001000101) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 534020 + ... + 537753.

It is an arithmetic number, because the mean of its divisors is an integer number (500518458).

Almost surely, 2^2001000191 is an apocalyptic number.

2001000191 is a deficient number, since it is larger than the sum of its proper divisors (1073641).

2001000191 is a wasteful number, since it uses less digits than its factorization.

2001000191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1073640.

The product of its (nonzero) digits is 18, while the sum is 14.

The square root of 2001000191 is about 44732.5406276013. The cubic root of 2001000191 is about 1260.1310418426.

Adding to 2001000191 its reverse (1910001002), we get a palindrome (3911001193).

The spelling of 2001000191 in words is "two billion, one million, one hundred ninety-one", and thus it is an aban number.