291287 has 2 divisors, whose sum is σ = 291288. Its totient is φ = 291286.

The previous prime is 291271. The next prime is 291293. The reversal of 291287 is 782192.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 291287 - 2⁴ = 291271 is a prime.

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 291287.

It is not a weakly prime, because it can be changed into another prime (291217) 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, 145643 + 145644.

It is an arithmetic number, because the mean of its divisors is an integer number (145644).

2²⁹¹²⁸⁷ is an apocalyptic number.

291287 is a deficient number, since it is larger than the sum of its proper divisors (1).

291287 is an equidigital number, since it uses as much as digits as its factorization.

291287 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2016, while the sum is 29.

The square root of 291287 is about 539.7101073725. The cubic root of 291287 is about 66.2888321056.

The spelling of 291287 in words is "two hundred ninety-one thousand, two hundred eighty-seven".