287319987 has 16 divisors (see below), whose sum is σ = 426494080. Its totient is φ = 191171016.

The previous prime is 287319983. The next prime is 287320037. The reversal of 287319987 is 789913782.

It is not a de Polignac number, because 287319987 - 2² = 287319983 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (287319983) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3948 + ... + 24294.

It is an arithmetic number, because the mean of its divisors is an integer number (26655880).

Almost surely, 2^287319987 is an apocalyptic number.

287319987 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

287319987 is a deficient number, since it is larger than the sum of its proper divisors (139174093).

287319987 is a wasteful number, since it uses less digits than its factorization.

287319987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20879 (or 20873 counting only the distinct ones).

The product of its digits is 1524096, while the sum is 54.

The square root of 287319987 is about 16950.5158328589. The cubic root of 287319987 is about 659.8652824210.

The spelling of 287319987 in words is "two hundred eighty-seven million, three hundred nineteen thousand, nine hundred eighty-seven".