191665140 has 48 divisors (see below), whose sum is σ = 568233792. Its totient is φ = 48103936.

The previous prime is 191665127. The next prime is 191665163. The reversal of 191665140 is 41566191.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 92934 + ... + 94973.

It is an arithmetic number, because the mean of its divisors is an integer number (11838204).

Almost surely, 2^191665140 is an apocalyptic number.

191665140 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

191665140 is an abundant number, since it is smaller than the sum of its proper divisors (376568652).

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

191665140 is a wasteful number, since it uses less digits than its factorization.

191665140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 187936 (or 187934 counting only the distinct ones).

The product of its (nonzero) digits is 6480, while the sum is 33.

The square root of 191665140 is about 13844.3179680330. The cubic root of 191665140 is about 576.5642498386.

The spelling of 191665140 in words is "one hundred ninety-one million, six hundred sixty-five thousand, one hundred forty".