9917990 has 32 divisors (see below), whose sum is σ = 18480960. Its totient is φ = 3830400.

The previous prime is 9917989. The next prime is 9918017. The reversal of 9917990 is 997199.

9917990 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 43196 + ... + 43424.

It is an arithmetic number, because the mean of its divisors is an integer number (577530).

Almost surely, 2^9917990 is an apocalyptic number.

9917990 is a deficient number, since it is larger than the sum of its proper divisors (8562970).

9917990 is a wasteful number, since it uses less digits than its factorization.

9917990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 368.

The product of its (nonzero) digits is 45927, while the sum is 44.

The square root of 9917990 is about 3149.2840456205. The cubic root of 9917990 is about 214.8529010031.

The spelling of 9917990 in words is "nine million, nine hundred seventeen thousand, nine hundred ninety".