9987971 has 8 divisors (see below), whose sum is σ = 11553024. Its totient is φ = 8457480.

The previous prime is 9987961. The next prime is 9987973. The reversal of 9987971 is 1797899.

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

It is a cyclic number.

It is not a de Polignac number, because 9987971 - 2¹⁸ = 9725827 is a prime.

It is not an unprimeable number, because it can be changed into a prime (9987973) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8015 + ... + 9176.

It is an arithmetic number, because the mean of its divisors is an integer number (1444128).

Almost surely, 2^9987971 is an apocalyptic number.

9987971 is a deficient number, since it is larger than the sum of its proper divisors (1565053).

9987971 is a wasteful number, since it uses less digits than its factorization.

9987971 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17281.

The product of its digits is 285768, while the sum is 50.

The square root of 9987971 is about 3160.3751359609. The cubic root of 9987971 is about 215.3570486926.

The spelling of 9987971 in words is "nine million, nine hundred eighty-seven thousand, nine hundred seventy-one".