9999171827 has 2 divisors, whose sum is σ = 9999171828. Its totient is φ = 9999171826.

The previous prime is 9999171803. The next prime is 9999171829. The reversal of 9999171827 is 7281719999.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 9999171827 - 2¹⁰ = 9999170803 is a prime.

Together with 9999171829, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 9999171827.

It is not a weakly prime, because it can be changed into another prime (9999171829) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4999585913 + 4999585914.

It is an arithmetic number, because the mean of its divisors is an integer number (4999585914).

Almost surely, 2^9999171827 is an apocalyptic number.

9999171827 is a deficient number, since it is larger than the sum of its proper divisors (1).

9999171827 is an equidigital number, since it uses as much as digits as its factorization.

9999171827 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5143824, while the sum is 62.

The square root of 9999171827 is about 99995.8590492626. The cubic root of 9999171827 is about 2154.3752135686.

The spelling of 9999171827 in words is "nine billion, nine hundred ninety-nine million, one hundred seventy-one thousand, eight hundred twenty-seven".