9789987 has 8 divisors (see below), whose sum is σ = 13094080. Its totient is φ = 6506280.

The previous prime is 9789971. The next prime is 9789991. The reversal of 9789987 is 7899879.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 9789987 - 2⁴ = 9789971 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (9789937) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3937 + ... + 5922.

It is an arithmetic number, because the mean of its divisors is an integer number (1636760).

Almost surely, 2^9789987 is an apocalyptic number.

9789987 is a deficient number, since it is larger than the sum of its proper divisors (3304093).

9789987 is a wasteful number, since it uses less digits than its factorization.

9789987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10193.

The product of its digits is 2286144, while the sum is 57.

The square root of 9789987 is about 3128.8954920227. The cubic root of 9789987 is about 213.9245883879.

The spelling of 9789987 in words is "nine million, seven hundred eighty-nine thousand, nine hundred eighty-seven".