191001660 has 48 divisors (see below), whose sum is σ = 558061056. Its totient is φ = 48718912.

The previous prime is 191001649. The next prime is 191001667. The reversal of 191001660 is 66100191.

191001660 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a self number, because there is not a number n which added to its sum of digits gives 191001660.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (191001667) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 67824 + ... + 70583.

It is an arithmetic number, because the mean of its divisors is an integer number (11626272).

Almost surely, 2^191001660 is an apocalyptic number.

191001660 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

191001660 is an abundant number, since it is smaller than the sum of its proper divisors (367059396).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

191001660 is a wasteful number, since it uses less digits than its factorization.

191001660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 138442 (or 138440 counting only the distinct ones).

The product of its (nonzero) digits is 324, while the sum is 24.

The square root of 191001660 is about 13820.3350176470. The cubic root of 191001660 is about 575.8981904357.

The spelling of 191001660 in words is "one hundred ninety-one million, one thousand, six hundred sixty".