171905983 has 2 divisors, whose sum is σ = 171905984. Its totient is φ = 171905982.

The previous prime is 171905963. The next prime is 171906029. The reversal of 171905983 is 389509171.

It is a weak prime.

It is an emirp because it is prime and its reverse (389509171) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 171905983 - 2²¹ = 169808831 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (171905953) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 85952991 + 85952992.

It is an arithmetic number, because the mean of its divisors is an integer number (85952992).

Almost surely, 2^171905983 is an apocalyptic number.

171905983 is a deficient number, since it is larger than the sum of its proper divisors (1).

171905983 is an equidigital number, since it uses as much as digits as its factorization.

171905983 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 68040, while the sum is 43.

The square root of 171905983 is about 13111.2921941356. The cubic root of 171905983 is about 556.0284293988.

The spelling of 171905983 in words is "one hundred seventy-one million, nine hundred five thousand, nine hundred eighty-three".