9821117249 has 2 divisors, whose sum is σ = 9821117250. Its totient is φ = 9821117248.

The previous prime is 9821117221. The next prime is 9821117261. The reversal of 9821117249 is 9427111289.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 8900601649 + 920515600 = 94343^2 + 30340^2 .

It is an emirp because it is prime and its reverse (9427111289) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 9821117249 - 2²⁴ = 9804340033 is a prime.

It is not a weakly prime, because it can be changed into another prime (9821117149) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4910558624 + 4910558625.

It is an arithmetic number, because the mean of its divisors is an integer number (4910558625).

Almost surely, 2^9821117249 is an apocalyptic number.

It is an amenable number.

9821117249 is a deficient number, since it is larger than the sum of its proper divisors (1).

9821117249 is an equidigital number, since it uses as much as digits as its factorization.

9821117249 is an evil number, because the sum of its binary digits is even.

The product of its digits is 72576, while the sum is 44.

The square root of 9821117249 is about 99101.5501846465. The cubic root of 9821117249 is about 2141.5109462948.

The spelling of 9821117249 in words is "nine billion, eight hundred twenty-one million, one hundred seventeen thousand, two hundred forty-nine".