287631391 has 2 divisors, whose sum is σ = 287631392. Its totient is φ = 287631390.

The previous prime is 287631373. The next prime is 287631397. The reversal of 287631391 is 193136782.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 287631391 - 2¹³ = 287623199 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (287631397) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 143815695 + 143815696.

It is an arithmetic number, because the mean of its divisors is an integer number (143815696).

Almost surely, 2^287631391 is an apocalyptic number.

287631391 is a deficient number, since it is larger than the sum of its proper divisors (1).

287631391 is an equidigital number, since it uses as much as digits as its factorization.

287631391 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 54432, while the sum is 40.

The square root of 287631391 is about 16959.6990244521. The cubic root of 287631391 is about 660.1035887299.

The spelling of 287631391 in words is "two hundred eighty-seven million, six hundred thirty-one thousand, three hundred ninety-one".