9991324757 has 2 divisors, whose sum is σ = 9991324758. Its totient is φ = 9991324756.

The previous prime is 9991324753. The next prime is 9991324771. The reversal of 9991324757 is 7574231999.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6078697156 + 3912627601 = 77966^2 + 62551^2 .

It is a cyclic number.

It is not a de Polignac number, because 9991324757 - 2² = 9991324753 is a prime.

It is a super-2 number, since 2×9991324757² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9991324751) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4995662378 + 4995662379.

It is an arithmetic number, because the mean of its divisors is an integer number (4995662379).

Almost surely, 2^9991324757 is an apocalyptic number.

It is an amenable number.

9991324757 is a deficient number, since it is larger than the sum of its proper divisors (1).

9991324757 is an equidigital number, since it uses as much as digits as its factorization.

9991324757 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4286520, while the sum is 56.

The square root of 9991324757 is about 99956.6143734370. The cubic root of 9991324757 is about 2153.8115016380.

The spelling of 9991324757 in words is "nine billion, nine hundred ninety-one million, three hundred twenty-four thousand, seven hundred fifty-seven".