861906 has 8 divisors (see below), whose sum is σ = 1723824. Its totient is φ = 287300.

The previous prime is 861901. The next prime is 861907. The reversal of 861906 is 609168.

861906 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

861906 is an admirable number.

It is an Ulam number.

It is not an unprimeable number, because it can be changed into a prime (861901) by changing a digit.

861906 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 71820 + ... + 71831.

It is an arithmetic number, because the mean of its divisors is an integer number (215478).

2⁸⁶¹⁹⁰⁶ is an apocalyptic number.

861906 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

861906 is a wasteful number, since it uses less digits than its factorization.

861906 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 143656.

The product of its (nonzero) digits is 2592, while the sum is 30.

The square root of 861906 is about 928.3889271205. The cubic root of 861906 is about 95.1670560162.

The spelling of 861906 in words is "eight hundred sixty-one thousand, nine hundred six".