861667 has 4 divisors (see below), whose sum is σ = 867600. Its totient is φ = 855736.

The previous prime is 861659. The next prime is 861691. The reversal of 861667 is 766168.

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 861667 - 2³ = 861659 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (861617) 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, 2743 + ... + 3040.

It is an arithmetic number, because the mean of its divisors is an integer number (216900).

2⁸⁶¹⁶⁶⁷ is an apocalyptic number.

861667 is a deficient number, since it is larger than the sum of its proper divisors (5933).

861667 is a wasteful number, since it uses less digits than its factorization.

861667 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5932.

The product of its digits is 12096, while the sum is 34.

The square root of 861667 is about 928.2602005903. The cubic root of 861667 is about 95.1582588353.

The spelling of 861667 in words is "eight hundred sixty-one thousand, six hundred sixty-seven".