861668 has 6 divisors (see below), whose sum is σ = 1507926. Its totient is φ = 430832.

The previous prime is 861659. The next prime is 861691. The reversal of 861668 is 866168.

861668 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 861184 + 484 = 928^2 + 22^2 .

It is an unprimeable number.

861668 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 as a sum of consecutive naturals, namely, 107705 + ... + 107712.

It is an arithmetic number, because the mean of its divisors is an integer number (251321).

2⁸⁶¹⁶⁶⁸ is an apocalyptic number.

It is an amenable number.

861668 is a deficient number, since it is larger than the sum of its proper divisors (646258).

861668 is a wasteful number, since it uses less digits than its factorization.

861668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 215421 (or 215419 counting only the distinct ones).

The product of its digits is 13824, while the sum is 35.

The square root of 861668 is about 928.2607392322. The cubic root of 861668 is about 95.1582956470.

The spelling of 861668 in words is "eight hundred sixty-one thousand, six hundred sixty-eight".