851231 has 2 divisors, whose sum is σ = 851232. Its totient is φ = 851230.

The previous prime is 851209. The next prime is 851239. The reversal of 851231 is 132158.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 851231 - 2¹⁰ = 850207 is a prime.

It is a super-2 number, since 2×851231² = 1449188430722, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 851231.

It is not a weakly prime, because it can be changed into another prime (851239) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 425615 + 425616.

It is an arithmetic number, because the mean of its divisors is an integer number (425616).

2⁸⁵¹²³¹ is an apocalyptic number.

851231 is a deficient number, since it is larger than the sum of its proper divisors (1).

851231 is an equidigital number, since it uses as much as digits as its factorization.

851231 is an evil number, because the sum of its binary digits is even.

The product of its digits is 240, while the sum is 20.

The square root of 851231 is about 922.6218076764. The cubic root of 851231 is about 94.7725305707.

Adding to 851231 its reverse (132158), we get a palindrome (983389).

The spelling of 851231 in words is "eight hundred fifty-one thousand, two hundred thirty-one".