391388287 has 2 divisors, whose sum is σ = 391388288. Its totient is φ = 391388286.

The previous prime is 391388273. The next prime is 391388303. The reversal of 391388287 is 782883193.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 391388287 - 2¹⁵ = 391355519 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 391388287.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (391380287) 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, 195694143 + 195694144.

It is an arithmetic number, because the mean of its divisors is an integer number (195694144).

Almost surely, 2^391388287 is an apocalyptic number.

391388287 is a deficient number, since it is larger than the sum of its proper divisors (1).

391388287 is an equidigital number, since it uses as much as digits as its factorization.

391388287 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 580608, while the sum is 49.

The square root of 391388287 is about 19783.5357557743. The cubic root of 391388287 is about 731.4802559089.

The spelling of 391388287 in words is "three hundred ninety-one million, three hundred eighty-eight thousand, two hundred eighty-seven".