9787978 has 8 divisors (see below), whose sum is σ = 14736960. Its totient is φ = 4875660.

The previous prime is 9787969. The next prime is 9787991. The reversal of 9787978 is 8797879.

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

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 8488 + ... + 9571.

It is an arithmetic number, because the mean of its divisors is an integer number (1842120).

Almost surely, 2^9787978 is an apocalyptic number.

9787978 is a deficient number, since it is larger than the sum of its proper divisors (4948982).

9787978 is a wasteful number, since it uses less digits than its factorization.

9787978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18332.

The product of its digits is 1778112, while the sum is 55.

The square root of 9787978 is about 3128.5744357455. The cubic root of 9787978 is about 213.9099542554.

Subtracting from 9787978 its reverse (8797879), we obtain a palindrome (990099).

The spelling of 9787978 in words is "nine million, seven hundred eighty-seven thousand, nine hundred seventy-eight".