9840945509 has 4 divisors (see below), whose sum is σ = 9847814316. Its totient is φ = 9834076704.

The previous prime is 9840945473. The next prime is 9840945511. The reversal of 9840945509 is 9055490489.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 3779544484 + 6061401025 = 61478^2 + 77855^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-9840945509 is a prime.

It is a super-2 number, since 2×9840945509² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9840945589) 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, 3432254 + ... + 3435119.

It is an arithmetic number, because the mean of its divisors is an integer number (2461953579).

Almost surely, 2^9840945509 is an apocalyptic number.

It is an amenable number.

9840945509 is a deficient number, since it is larger than the sum of its proper divisors (6868807).

9840945509 is a wasteful number, since it uses less digits than its factorization.

9840945509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6868806.

The product of its (nonzero) digits is 2332800, while the sum is 53.

The square root of 9840945509 is about 99201.5398519600. The cubic root of 9840945509 is about 2142.9511725060.

The spelling of 9840945509 in words is "nine billion, eight hundred forty million, nine hundred forty-five thousand, five hundred nine".