999816871 has 2 divisors, whose sum is σ = 999816872. Its totient is φ = 999816870.

The previous prime is 999816799. The next prime is 999816893. The reversal of 999816871 is 178618999.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 999816871 - 2²¹ = 997719719 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (999816071) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499908435 + 499908436.

It is an arithmetic number, because the mean of its divisors is an integer number (499908436).

Almost surely, 2^999816871 is an apocalyptic number.

999816871 is a deficient number, since it is larger than the sum of its proper divisors (1).

999816871 is an equidigital number, since it uses as much as digits as its factorization.

999816871 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1959552, while the sum is 58.

The square root of 999816871 is about 31619.8809453799. The cubic root of 999816871 is about 999.9389532734.

The spelling of 999816871 in words is "nine hundred ninety-nine million, eight hundred sixteen thousand, eight hundred seventy-one".