9999988866631 has 2 divisors, whose sum is σ = 9999988866632. Its totient is φ = 9999988866630.

The previous prime is 9999988866599. The next prime is 9999988866667. The reversal of 9999988866631 is 1366688899999.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 9999988866631 - 2⁵ = 9999988866599 is a prime.

It is a super-2 number, since 2×9999988866631² (a number of 27 digits) contains 22 as substring.

It is a nialpdrome in base 10.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9999988866731) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4999994433315 + 4999994433316.

It is an arithmetic number, because the mean of its divisors is an integer number (4999994433316).

Almost surely, 2^{9999988866631} is an apocalyptic number.

9999988866631 is a deficient number, since it is larger than the sum of its proper divisors (1).

9999988866631 is an equidigital number, since it uses as much as digits as its factorization.

9999988866631 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 19591041024, while the sum is 91.

The spelling of 9999988866631 in words is "nine trillion, nine hundred ninety-nine billion, nine hundred eighty-eight million, eight hundred sixty-six thousand, six hundred thirty-one".