2991171 has 4 divisors (see below), whose sum is σ = 3988232. Its totient is φ = 1994112.

The previous prime is 2991143. The next prime is 2991187. The reversal of 2991171 is 1711992.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 2991171 - 2⁵ = 2991139 is a prime.

It is a D-number.

It is the 1730-th Hogben number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2991671) by changing a digit.

It is a nontrivial repunit in base 1729.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 498526 + ... + 498531.

It is an arithmetic number, because the mean of its divisors is an integer number (997058).

2^2991171 is an apocalyptic number.

2991171 is a deficient number, since it is larger than the sum of its proper divisors (997061).

2991171 is an equidigital number, since it uses as much as digits as its factorization.

2991171 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 997060.

The product of its digits is 1134, while the sum is 30.

The square root of 2991171 is about 1729.5002168257. The cubic root of 2991171 is about 144.0833333240.

The spelling of 2991171 in words is "two million, nine hundred ninety-one thousand, one hundred seventy-one".