9998787 has 4 divisors (see below), whose sum is σ = 13331720. Its totient is φ = 6665856.

The previous prime is 9998777. The next prime is 9998797. The reversal of 9998787 is 7878999.

It is a happy number.

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

It is an interprime number because it is at equal distance from previous prime (9998777) and next prime (9998797).

It is not a de Polignac number, because 9998787 - 2¹⁶ = 9933251 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 (9998777) 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, 1666462 + ... + 1666467.

It is an arithmetic number, because the mean of its divisors is an integer number (3332930).

Almost surely, 2^9998787 is an apocalyptic number.

9998787 is a deficient number, since it is larger than the sum of its proper divisors (3332933).

9998787 is a wasteful number, since it uses less digits than its factorization.

9998787 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3332932.

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

The square root of 9998787 is about 3162.0858622118. The cubic root of 9998787 is about 215.4347575533.

The spelling of 9998787 in words is "nine million, nine hundred ninety-eight thousand, seven hundred eighty-seven".