640111191 has 8 divisors (see below), whose sum is σ = 856498560. Its totient is φ = 425232312.

The previous prime is 640111177. The next prime is 640111193. The reversal of 640111191 is 191111046.

640111191 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 640111191 - 2²⁶ = 573002327 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640111193) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 376131 + ... + 377828.

It is an arithmetic number, because the mean of its divisors is an integer number (107062320).

Almost surely, 2^640111191 is an apocalyptic number.

640111191 is a deficient number, since it is larger than the sum of its proper divisors (216387369).

640111191 is a wasteful number, since it uses less digits than its factorization.

640111191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 754245.

The product of its (nonzero) digits is 216, while the sum is 24.

The square root of 640111191 is about 25300.4187910003. The cubic root of 640111191 is about 861.8237801536.

The spelling of 640111191 in words is "six hundred forty million, one hundred eleven thousand, one hundred ninety-one".