9978448769 has 2 divisors, whose sum is σ = 9978448770. Its totient is φ = 9978448768.

The previous prime is 9978448723. The next prime is 9978448771. The reversal of 9978448769 is 9678448799.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6412806400 + 3565642369 = 80080^2 + 59713^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-9978448769 is a prime.

It is a super-2 number, since 2×9978448769² (a number of 21 digits) contains 22 as substring.

It is a Sophie Germain prime.

Together with 9978448771, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (9978441769) 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, 4989224384 + 4989224385.

It is an arithmetic number, because the mean of its divisors is an integer number (4989224385).

Almost surely, 2^9978448769 is an apocalyptic number.

It is an amenable number.

9978448769 is a deficient number, since it is larger than the sum of its proper divisors (1).

9978448769 is an equidigital number, since it uses as much as digits as its factorization.

9978448769 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 219469824, while the sum is 71.

The square root of 9978448769 is about 99892.1857254110. The cubic root of 9978448769 is about 2152.8858862215.

The spelling of 9978448769 in words is "nine billion, nine hundred seventy-eight million, four hundred forty-eight thousand, seven hundred sixty-nine".