191640 has 32 divisors (see below), whose sum is σ = 575280. Its totient is φ = 51072.

The previous prime is 191627. The next prime is 191657. The reversal of 191640 is 46191.

191640 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 679 + ... + 918.

2¹⁹¹⁶⁴⁰ is an apocalyptic number.

191640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

191640 is an abundant number, since it is smaller than the sum of its proper divisors (383640).

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

191640 is a wasteful number, since it uses less digits than its factorization.

191640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1611 (or 1607 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 21.

The square root of 191640 is about 437.7670613466. The cubic root of 191640 is about 57.6539040144.

The spelling of 191640 in words is "one hundred ninety-one thousand, six hundred forty".