9961985 has 16 divisors (see below), whose sum is σ = 13728960. Its totient is φ = 6863040.

The previous prime is 9961981. The next prime is 9962003. The reversal of 9961985 is 5891699.

It is not a de Polignac number, because 9961985 - 2² = 9961981 is a prime.

It is a super-2 number, since 2×9961985² = 198482290280450, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (9961981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3722 + ... + 5811.

It is an arithmetic number, because the mean of its divisors is an integer number (858060).

Almost surely, 2^9961985 is an apocalyptic number.

9961985 is a gapful number since it is divisible by the number (95) formed by its first and last digit.

It is an amenable number.

9961985 is a deficient number, since it is larger than the sum of its proper divisors (3766975).

9961985 is a wasteful number, since it uses less digits than its factorization.

9961985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9568.

The product of its digits is 174960, while the sum is 47.

The square root of 9961985 is about 3156.2612376038. The cubic root of 9961985 is about 215.1701195482.

The spelling of 9961985 in words is "nine million, nine hundred sixty-one thousand, nine hundred eighty-five".