660109191 has 32 divisors (see below), whose sum is σ = 1060546560. Its totient is φ = 356770656.

The previous prime is 660109159. The next prime is 660109199. The reversal of 660109191 is 191901066.

It is not a de Polignac number, because 660109191 - 2⁵ = 660109159 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (660109199) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 376980 + ... + 378726.

It is an arithmetic number, because the mean of its divisors is an integer number (33142080).

Almost surely, 2^660109191 is an apocalyptic number.

660109191 is a deficient number, since it is larger than the sum of its proper divisors (400437369).

660109191 is a wasteful number, since it uses less digits than its factorization.

660109191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2723.

The product of its (nonzero) digits is 2916, while the sum is 33.

The square root of 660109191 is about 25692.5901963971. The cubic root of 660109191 is about 870.7067806625.

The spelling of 660109191 in words is "six hundred sixty million, one hundred nine thousand, one hundred ninety-one".