851243 has 4 divisors (see below), whose sum is σ = 856128. Its totient is φ = 846360.

The previous prime is 851239. The next prime is 851251. The reversal of 851243 is 342158.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 342158 = 2 ⋅171079.

It is a cyclic number.

It is not a de Polignac number, because 851243 - 2² = 851239 is a prime.

It is a super-2 number, since 2×851243² = 1449229290098, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (851203) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2171 + ... + 2532.

It is an arithmetic number, because the mean of its divisors is an integer number (214032).

2⁸⁵¹²⁴³ is an apocalyptic number.

851243 is a deficient number, since it is larger than the sum of its proper divisors (4885).

851243 is a wasteful number, since it uses less digits than its factorization.

851243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4884.

The product of its digits is 960, while the sum is 23.

The square root of 851243 is about 922.6283108598. The cubic root of 851243 is about 94.7729759121.

The spelling of 851243 in words is "eight hundred fifty-one thousand, two hundred forty-three".