551231 has 2 divisors, whose sum is σ = 551232. Its totient is φ = 551230.

The previous prime is 551219. The next prime is 551233. The reversal of 551231 is 132155.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-551231 is a prime.

It is a super-2 number, since 2×551231² = 607711230722, which contains 22 as substring.

It is a Sophie Germain prime.

Together with 551233, it forms a pair of twin primes.

It is a Chen prime.

It is a plaindrome in base 12.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (551233) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 275615 + 275616.

It is an arithmetic number, because the mean of its divisors is an integer number (275616).

2⁵⁵¹²³¹ is an apocalyptic number.

551231 is a deficient number, since it is larger than the sum of its proper divisors (1).

551231 is an equidigital number, since it uses as much as digits as its factorization.

551231 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 150, while the sum is 17.

The square root of 551231 is about 742.4493248701. The cubic root of 551231 is about 81.9932078451.

Adding to 551231 its reverse (132155), we get a palindrome (683386).

The spelling of 551231 in words is "five hundred fifty-one thousand, two hundred thirty-one".