861847 has 4 divisors (see below), whose sum is σ = 984976. Its totient is φ = 738720.

The previous prime is 861829. The next prime is 861853. The reversal of 861847 is 748168.

It is a happy number.

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 861847 - 2⁷ = 861719 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (861857) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 61554 + ... + 61567.

It is an arithmetic number, because the mean of its divisors is an integer number (246244).

2⁸⁶¹⁸⁴⁷ is an apocalyptic number.

861847 is a deficient number, since it is larger than the sum of its proper divisors (123129).

861847 is a wasteful number, since it uses less digits than its factorization.

861847 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 123128.

The product of its digits is 10752, while the sum is 34.

The square root of 861847 is about 928.3571511008. The cubic root of 861847 is about 95.1648844784.

The spelling of 861847 in words is "eight hundred sixty-one thousand, eight hundred forty-seven".