9945978 has 32 divisors (see below), whose sum is σ = 23470080. Its totient is φ = 2749680.

The previous prime is 9945977. The next prime is 9945979. The reversal of 9945978 is 8795499.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (9945977) and next prime (9945979).

It is a self number, because there is not a number n which added to its sum of digits gives 9945978.

It is not an unprimeable number, because it can be changed into a prime (9945977) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2518 + ... + 5121.

It is an arithmetic number, because the mean of its divisors is an integer number (733440).

Almost surely, 2^9945978 is an apocalyptic number.

9945978 is an abundant number, since it is smaller than the sum of its proper divisors (13524102).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

9945978 is a wasteful number, since it uses less digits than its factorization.

9945978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7682.

The product of its digits is 816480, while the sum is 51.

The square root of 9945978 is about 3153.7244648193. The cubic root of 9945978 is about 215.0548120571.

The spelling of 9945978 in words is "nine million, nine hundred forty-five thousand, nine hundred seventy-eight".