9643987 has 4 divisors (see below), whose sum is σ = 9650200. Its totient is φ = 9637776.

The previous prime is 9643973. The next prime is 9644003. The reversal of 9643987 is 7893469.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 7893469 = 37 ⋅213337.

It is a cyclic number.

It is not a de Polignac number, because 9643987 - 2¹⁹ = 9119699 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (9643927) 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, 1468 + ... + 4630.

It is an arithmetic number, because the mean of its divisors is an integer number (2412550).

Almost surely, 2^9643987 is an apocalyptic number.

9643987 is a deficient number, since it is larger than the sum of its proper divisors (6213).

9643987 is a wasteful number, since it uses less digits than its factorization.

9643987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6212.

The product of its digits is 326592, while the sum is 46.

The square root of 9643987 is about 3105.4769359955. The cubic root of 9643987 is about 212.8558246115.

The spelling of 9643987 in words is "nine million, six hundred forty-three thousand, nine hundred eighty-seven".