9978975 has 18 divisors (see below), whose sum is σ = 17873856. Its totient is φ = 5322000.

The previous prime is 9978961. The next prime is 9978989. The reversal of 9978975 is 5798799.

It is an interprime number because it is at equal distance from previous prime (9978961) and next prime (9978989).

It is not a de Polignac number, because 9978975 - 2⁴ = 9978959 is a prime.

It is a congruent number.

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 17 ways as a sum of consecutive naturals, for example, 21951 + ... + 22400.

It is an arithmetic number, because the mean of its divisors is an integer number (992992).

Almost surely, 2^9978975 is an apocalyptic number.

9978975 is a deficient number, since it is larger than the sum of its proper divisors (7894881).

9978975 is a wasteful number, since it uses less digits than its factorization.

9978975 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44367 (or 44359 counting only the distinct ones).

The product of its digits is 1428840, while the sum is 54.

The square root of 9978975 is about 3158.9515665803. The cubic root of 9978975 is about 215.2923730961.

The spelling of 9978975 in words is "nine million, nine hundred seventy-eight thousand, nine hundred seventy-five".