287998993 has 4 divisors (see below), whose sum is σ = 294696688. Its totient is φ = 281301300.

The previous prime is 287998987. The next prime is 287998999. The reversal of 287998993 is 399899782.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (287998987) and next prime (287998999).

It is a cyclic number.

It is not a de Polignac number, because 287998993 - 2⁹ = 287998481 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (287998999) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3348783 + ... + 3348868.

It is an arithmetic number, because the mean of its divisors is an integer number (73674172).

Almost surely, 2^287998993 is an apocalyptic number.

It is an amenable number.

287998993 is a deficient number, since it is larger than the sum of its proper divisors (6697695).

287998993 is an equidigital number, since it uses as much as digits as its factorization.

287998993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6697694.

The product of its digits is 17635968, while the sum is 64.

The square root of 287998993 is about 16970.5330794292. The cubic root of 287998993 is about 660.3846800927.

The spelling of 287998993 in words is "two hundred eighty-seven million, nine hundred ninety-eight thousand, nine hundred ninety-three".