99897989171 has 2 divisors, whose sum is σ = 99897989172. Its totient is φ = 99897989170.

The previous prime is 99897989123. The next prime is 99897989183. The reversal of 99897989171 is 17198979899.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-99897989171 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 99897989092 and 99897989101.

It is not a weakly prime, because it can be changed into another prime (99897989371) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49948994585 + 49948994586.

It is an arithmetic number, because the mean of its divisors is an integer number (49948994586).

Almost surely, 2^99897989171 is an apocalyptic number.

99897989171 is a deficient number, since it is larger than the sum of its proper divisors (1).

99897989171 is an equidigital number, since it uses as much as digits as its factorization.

99897989171 is an evil number, because the sum of its binary digits is even.

The product of its digits is 185177664, while the sum is 77.

The spelling of 99897989171 in words is "ninety-nine billion, eight hundred ninety-seven million, nine hundred eighty-nine thousand, one hundred seventy-one".