9918728 has 16 divisors (see below), whose sum is σ = 18645180. Its totient is φ = 4946688.

The previous prime is 9918721. The next prime is 9918743. The reversal of 9918728 is 8278199.

It can be written as a sum of positive squares in 2 ways, for example, as 7300804 + 2617924 = 2702^2 + 1618^2 .

It is not an unprimeable number, because it can be changed into a prime (9918721) 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, 2300 + ... + 5012.

Almost surely, 2^9918728 is an apocalyptic number.

It is an amenable number.

9918728 is a deficient number, since it is larger than the sum of its proper divisors (8726452).

9918728 is a wasteful number, since it uses less digits than its factorization.

9918728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3176 (or 3172 counting only the distinct ones).

The product of its digits is 72576, while the sum is 44.

The square root of 9918728 is about 3149.4012129292. The cubic root of 9918728 is about 214.8582299561.

The spelling of 9918728 in words is "nine million, nine hundred eighteen thousand, seven hundred twenty-eight".