9905985 has 48 divisors (see below), whose sum is σ = 19004544. Its totient is φ = 4747776.

The previous prime is 9905981. The next prime is 9905989. The reversal of 9905985 is 5895099.

It is an interprime number because it is at equal distance from previous prime (9905981) and next prime (9905989).

It is not a de Polignac number, because 9905985 - 2² = 9905981 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an Ulam number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 9905985.

It is not an unprimeable number, because it can be changed into a prime (9905981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 17314 + ... + 17876.

It is an arithmetic number, because the mean of its divisors is an integer number (395928).

Almost surely, 2^9905985 is an apocalyptic number.

It is an amenable number.

9905985 is a deficient number, since it is larger than the sum of its proper divisors (9098559).

9905985 is a wasteful number, since it uses less digits than its factorization.

9905985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 614 (or 611 counting only the distinct ones).

The product of its (nonzero) digits is 145800, while the sum is 45.

The square root of 9905985 is about 3147.3774797440. The cubic root of 9905985 is about 214.7661781064.

The spelling of 9905985 in words is "nine million, nine hundred five thousand, nine hundred eighty-five".