861604 has 12 divisors (see below), whose sum is σ = 1540224. Its totient is φ = 421544.

The previous prime is 861599. The next prime is 861613. The reversal of 861604 is 406168.

It is a super-2 number, since 2×861604² = 1484722905632, which contains 22 as substring.

It is an unprimeable number.

861604 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, 2104 + ... + 2479.

It is an arithmetic number, because the mean of its divisors is an integer number (128352).

2⁸⁶¹⁶⁰⁴ is an apocalyptic number.

It is an amenable number.

861604 is a deficient number, since it is larger than the sum of its proper divisors (678620).

861604 is a wasteful number, since it uses less digits than its factorization.

861604 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4634 (or 4632 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 25.

The square root of 861604 is about 928.2262655194. The cubic root of 861604 is about 95.1559396423.

The spelling of 861604 in words is "eight hundred sixty-one thousand, six hundred four".