990171 has 48 divisors (see below), whose sum is σ = 1873920. Its totient is φ = 505440.

The previous prime is 990169. The next prime is 990179. The reversal of 990171 is 171099.

It is not a de Polignac number, because 990171 - 2¹ = 990169 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (990179) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 31926 + ... + 31956.

It is an arithmetic number, because the mean of its divisors is an integer number (39040).

2⁹⁹⁰¹⁷¹ is an apocalyptic number.

990171 is a gapful number since it is divisible by the number (91) formed by its first and last digit.

990171 is a deficient number, since it is larger than the sum of its proper divisors (883749).

990171 is a wasteful number, since it uses less digits than its factorization.

990171 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 73 (or 54 counting only the distinct ones).

The product of its (nonzero) digits is 567, while the sum is 27.

The square root of 990171 is about 995.0733641295. The cubic root of 990171 is about 99.6712873304.

The spelling of 990171 in words is "nine hundred ninety thousand, one hundred seventy-one".