9869765621 has 2 divisors, whose sum is σ = 9869765622. Its totient is φ = 9869765620.

The previous prime is 9869765603. The next prime is 9869765687. The reversal of 9869765621 is 1265679689.

9869765621 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5554720900 + 4315044721 = 74530^2 + 65689^2 .

It is an emirp because it is prime and its reverse (1265679689) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 9869765621 - 2⁶ = 9869765557 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9869705621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4934882810 + 4934882811.

It is an arithmetic number, because the mean of its divisors is an integer number (4934882811).

Almost surely, 2^9869765621 is an apocalyptic number.

It is an amenable number.

9869765621 is a deficient number, since it is larger than the sum of its proper divisors (1).

9869765621 is an equidigital number, since it uses as much as digits as its factorization.

9869765621 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9797760, while the sum is 59.

The square root of 9869765621 is about 99346.6940617553. The cubic root of 9869765621 is about 2145.0410767269.

The spelling of 9869765621 in words is "nine billion, eight hundred sixty-nine million, seven hundred sixty-five thousand, six hundred twenty-one".