9990078 has 16 divisors (see below), whose sum is σ = 22834560. Its totient is φ = 2854296.

The previous prime is 9990047. The next prime is 9990089. The reversal of 9990078 is 8700999.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (42), and also a Moran number because the ratio is a prime number: 237859 = 9990078 / (9 + 9 + 9 + 0 + 0 + 7 + 8).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 118888 + ... + 118971.

It is an arithmetic number, because the mean of its divisors is an integer number (1427160).

Almost surely, 2^9990078 is an apocalyptic number.

9990078 is an abundant number, since it is smaller than the sum of its proper divisors (12844482).

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

9990078 is a wasteful number, since it uses less digits than its factorization.

9990078 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 237871.

The product of its (nonzero) digits is 40824, while the sum is 42.

The square root of 9990078 is about 3160.7084648857. The cubic root of 9990078 is about 215.3721910874.

The spelling of 9990078 in words is "nine million, nine hundred ninety thousand, seventy-eight".