171985943 has 2 divisors, whose sum is σ = 171985944. Its totient is φ = 171985942.

The previous prime is 171985937. The next prime is 171985987. The reversal of 171985943 is 349589171.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 171985943 - 2¹⁴ = 171969559 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (171985903) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 85992971 + 85992972.

It is an arithmetic number, because the mean of its divisors is an integer number (85992972).

Almost surely, 2^171985943 is an apocalyptic number.

171985943 is a deficient number, since it is larger than the sum of its proper divisors (1).

171985943 is an equidigital number, since it uses as much as digits as its factorization.

171985943 is an evil number, because the sum of its binary digits is even.

The product of its digits is 272160, while the sum is 47.

The square root of 171985943 is about 13114.3411195531. The cubic root of 171985943 is about 556.1146260140.

The spelling of 171985943 in words is "one hundred seventy-one million, nine hundred eighty-five thousand, nine hundred forty-three".