165740191 has 16 divisors (see below), whose sum is σ = 182463840. Its totient is φ = 149847040.

The previous prime is 165740177. The next prime is 165740203. The reversal of 165740191 is 191047561.

It is a cyclic number.

It is not a de Polignac number, because 165740191 - 2¹¹ = 165738143 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165740171) 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, 111171 + ... + 112651.

It is an arithmetic number, because the mean of its divisors is an integer number (11403990).

Almost surely, 2^165740191 is an apocalyptic number.

165740191 is a deficient number, since it is larger than the sum of its proper divisors (16723649).

165740191 is a wasteful number, since it uses less digits than its factorization.

165740191 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1754.

The product of its (nonzero) digits is 7560, while the sum is 34.

The square root of 165740191 is about 12874.0122339541. The cubic root of 165740191 is about 549.2995943872.

The spelling of 165740191 in words is "one hundred sixty-five million, seven hundred forty thousand, one hundred ninety-one".