866545 has 4 divisors (see below), whose sum is σ = 1039860. Its totient is φ = 693232.

The previous prime is 866519. The next prime is 866573. The reversal of 866545 is 545668.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 215296 + 651249 = 464^2 + 807^2 .

It is a cyclic number.

It is not a de Polignac number, because 866545 - 2⁵ = 866513 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 866545.

It is an unprimeable number.

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, 86650 + ... + 86659.

It is an arithmetic number, because the mean of its divisors is an integer number (259965).

2⁸⁶⁶⁵⁴⁵ is an apocalyptic number.

It is an amenable number.

866545 is a deficient number, since it is larger than the sum of its proper divisors (173315).

866545 is a wasteful number, since it uses less digits than its factorization.

866545 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 173314.

The product of its digits is 28800, while the sum is 34.

The square root of 866545 is about 930.8839884755. The cubic root of 866545 is about 95.3374884763.

The spelling of 866545 in words is "eight hundred sixty-six thousand, five hundred forty-five".