855139 has 4 divisors (see below), whose sum is σ = 860256. Its totient is φ = 850024.

The previous prime is 855131. The next prime is 855143. The reversal of 855139 is 931558.

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 855139 - 2³ = 855131 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 855139.

It is not an unprimeable number, because it can be changed into a prime (855131) 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, 2299 + ... + 2644.

It is an arithmetic number, because the mean of its divisors is an integer number (215064).

2⁸⁵⁵¹³⁹ is an apocalyptic number.

855139 is a deficient number, since it is larger than the sum of its proper divisors (5117).

855139 is a wasteful number, since it uses less digits than its factorization.

855139 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5116.

The product of its digits is 5400, while the sum is 31.

The square root of 855139 is about 924.7372599825. The cubic root of 855139 is about 94.9173426917.

The spelling of 855139 in words is "eight hundred fifty-five thousand, one hundred thirty-nine".