4005871 has 4 divisors (see below), whose sum is σ = 4009912. Its totient is φ = 4001832.

The previous prime is 4005847. The next prime is 4005889. The reversal of 4005871 is 1785004.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 4005871 - 2⁵ = 4005839 is a prime.

It is a Duffinian number.

4005871 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4005821) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 601 + ... + 2893.

It is an arithmetic number, because the mean of its divisors is an integer number (1002478).

Almost surely, 2^4005871 is an apocalyptic number.

4005871 is a deficient number, since it is larger than the sum of its proper divisors (4041).

4005871 is a wasteful number, since it uses less digits than its factorization.

4005871 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4040.

The product of its (nonzero) digits is 1120, while the sum is 25.

The square root of 4005871 is about 2001.4672118224. The cubic root of 4005871 is about 158.8177308273.

The spelling of 4005871 in words is "four million, five thousand, eight hundred seventy-one".