861986 has 8 divisors (see below), whose sum is σ = 1334784. Its totient is φ = 417060.

The previous prime is 861979. The next prime is 861997. The reversal of 861986 is 689168.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6890 + ... + 7013.

It is an arithmetic number, because the mean of its divisors is an integer number (166848).

2⁸⁶¹⁹⁸⁶ is an apocalyptic number.

861986 is a deficient number, since it is larger than the sum of its proper divisors (472798).

861986 is a wasteful number, since it uses less digits than its factorization.

861986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13936.

The product of its digits is 20736, while the sum is 38.

The square root of 861986 is about 928.4320115119. The cubic root of 861986 is about 95.1700003160.

The spelling of 861986 in words is "eight hundred sixty-one thousand, nine hundred eighty-six".