2399987 has 4 divisors (see below), whose sum is σ = 2408016. Its totient is φ = 2391960.

The previous prime is 2399983. The next prime is 2399993. The reversal of 2399987 is 7899932.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 2399987 - 2² = 2399983 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2399983) 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 in 3 ways as a sum of consecutive naturals, for example, 3548 + ... + 4169.

It is an arithmetic number, because the mean of its divisors is an integer number (602004).

2^2399987 is an apocalyptic number.

2399987 is a deficient number, since it is larger than the sum of its proper divisors (8029).

2399987 is an equidigital number, since it uses as much as digits as its factorization.

2399987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8028.

The product of its digits is 244944, while the sum is 47.

The square root of 2399987 is about 1549.1891427453. The cubic root of 2399987 is about 133.8863482763.

Subtracting 2399987 from its reverse (7899932), we obtain a palindrome (5499945).

The spelling of 2399987 in words is "two million, three hundred ninety-nine thousand, nine hundred eighty-seven".