861671 has 4 divisors (see below), whose sum is σ = 869832. Its totient is φ = 853512.

The previous prime is 861659. The next prime is 861691. The reversal of 861671 is 176168.

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

It is a cyclic number.

It is not a de Polignac number, because 861671 - 2¹⁰ = 860647 is a prime.

It is a Duffinian number.

It is a plaindrome in base 12.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (861691) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3920 + ... + 4133.

It is an arithmetic number, because the mean of its divisors is an integer number (217458).

2⁸⁶¹⁶⁷¹ is an apocalyptic number.

861671 is a deficient number, since it is larger than the sum of its proper divisors (8161).

861671 is a wasteful number, since it uses less digits than its factorization.

861671 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8160.

The product of its digits is 2016, while the sum is 29.

The square root of 861671 is about 928.2623551561. The cubic root of 861671 is about 95.1584060819.

It can be divided in two parts, 86167 and 1, that added together give a palindrome (86168).

The spelling of 861671 in words is "eight hundred sixty-one thousand, six hundred seventy-one".