855563 has 4 divisors (see below), whose sum is σ = 859560. Its totient is φ = 851568.

The previous prime is 855527. The next prime is 855581. The reversal of 855563 is 365558.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 365558 = 2 ⋅182779.

It is a cyclic number.

It is not a de Polignac number, because 855563 - 2⁶ = 855499 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (855863) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1658 + ... + 2111.

It is an arithmetic number, because the mean of its divisors is an integer number (214890).

2⁸⁵⁵⁵⁶³ is an apocalyptic number.

855563 is a deficient number, since it is larger than the sum of its proper divisors (3997).

855563 is a wasteful number, since it uses less digits than its factorization.

855563 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3996.

The product of its digits is 18000, while the sum is 32.

The square root of 855563 is about 924.9664858794. The cubic root of 855563 is about 94.9330275896.

The spelling of 855563 in words is "eight hundred fifty-five thousand, five hundred sixty-three".