9987764609 has 2 divisors, whose sum is σ = 9987764610. Its totient is φ = 9987764608.

The previous prime is 9987764603. The next prime is 9987764627. The reversal of 9987764609 is 9064677899.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 9987004225 + 760384 = 99935^2 + 872^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-9987764609 is a prime.

It is a super-3 number, since 3×9987764609³ (a number of 31 digits) contains 333 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (9987764603) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4993882304 + 4993882305.

It is an arithmetic number, because the mean of its divisors is an integer number (4993882305).

Almost surely, 2^9987764609 is an apocalyptic number.

It is an amenable number.

9987764609 is a deficient number, since it is larger than the sum of its proper divisors (1).

9987764609 is an equidigital number, since it uses as much as digits as its factorization.

9987764609 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 41150592, while the sum is 65.

The square root of 9987764609 is about 99938.8043204440. The cubic root of 9987764609 is about 2153.5556530618. Note that the first 3 decimals are identical.

The spelling of 9987764609 in words is "nine billion, nine hundred eighty-seven million, seven hundred sixty-four thousand, six hundred nine".