231428287 has 2 divisors, whose sum is σ = 231428288. Its totient is φ = 231428286.

The previous prime is 231428261. The next prime is 231428297. The reversal of 231428287 is 782824132.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 231428287 - 2²³ = 223039679 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (231428257) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115714143 + 115714144.

It is an arithmetic number, because the mean of its divisors is an integer number (115714144).

Almost surely, 2^231428287 is an apocalyptic number.

231428287 is a deficient number, since it is larger than the sum of its proper divisors (1).

231428287 is an equidigital number, since it uses as much as digits as its factorization.

231428287 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 43008, while the sum is 37.

The square root of 231428287 is about 15212.7672367653. The cubic root of 231428287 is about 613.9582133353.

The spelling of 231428287 in words is "two hundred thirty-one million, four hundred twenty-eight thousand, two hundred eighty-seven".