9990818 has 8 divisors (see below), whose sum is σ = 15269148. Its totient is φ = 4901104.

The previous prime is 9990817. The next prime is 9990821. The reversal of 9990818 is 8180999.

It can be written as a sum of positive squares in 2 ways, for example, as 7689529 + 2301289 = 2773^2 + 1517^2 .

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

It is not an unprimeable number, because it can be changed into a prime (9990811) 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, 47021 + ... + 47232.

Almost surely, 2^9990818 is an apocalyptic number.

9990818 is a deficient number, since it is larger than the sum of its proper divisors (5278330).

9990818 is a wasteful number, since it uses less digits than its factorization.

9990818 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 94308.

The product of its (nonzero) digits is 46656, while the sum is 44.

The square root of 9990818 is about 3160.8255250804. The cubic root of 9990818 is about 215.3775087464.

The spelling of 9990818 in words is "nine million, nine hundred ninety thousand, eight hundred eighteen".