171995990 has 8 divisors (see below), whose sum is σ = 309592800. Its totient is φ = 68798392.

The previous prime is 171995977. The next prime is 171996007. The reversal of 171995990 is 99599171.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8599790 + ... + 8599809.

It is an arithmetic number, because the mean of its divisors is an integer number (38699100).

Almost surely, 2^171995990 is an apocalyptic number.

171995990 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

171995990 is a deficient number, since it is larger than the sum of its proper divisors (137596810).

171995990 is a wasteful number, since it uses less digits than its factorization.

171995990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17199606.

The product of its (nonzero) digits is 229635, while the sum is 50.

The square root of 171995990 is about 13114.7241678962. The cubic root of 171995990 is about 556.1254547573.

The spelling of 171995990 in words is "one hundred seventy-one million, nine hundred ninety-five thousand, nine hundred ninety".