855951 has 4 divisors (see below), whose sum is σ = 1141272. Its totient is φ = 570632.

The previous prime is 855947. The next prime is 855983. The reversal of 855951 is 159558.

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 855951 - 2² = 855947 is a prime.

It is a super-2 number, since 2×855951² = 1465304228802, which contains 22 as substring.

It is a D-number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (855901) 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, 142656 + ... + 142661.

It is an arithmetic number, because the mean of its divisors is an integer number (285318).

2⁸⁵⁵⁹⁵¹ is an apocalyptic number.

855951 is a deficient number, since it is larger than the sum of its proper divisors (285321).

855951 is a wasteful number, since it uses less digits than its factorization.

855951 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 285320.

The product of its digits is 9000, while the sum is 33.

The square root of 855951 is about 925.1761994345. The cubic root of 855951 is about 94.9473762107.

Subtracting from 855951 its product of digits (9000), we obtain a triangular number (846951 = T₁₃₀₁).

The spelling of 855951 in words is "eight hundred fifty-five thousand, nine hundred fifty-one".