99999999991867 has 2 divisors, whose sum is σ = 99999999991868. Its totient is φ = 99999999991866.

The previous prime is 99999999991831. The next prime is 99999999991877. The reversal of 99999999991867 is 76819999999999.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-99999999991867 is a prime.

It is a super-2 number, since 2×99999999991867² (a number of 29 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (99999999991807) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49999999995933 + 49999999995934.

It is an arithmetic number, because the mean of its divisors is an integer number (49999999995934).

Almost surely, 2^{99999999991867} is an apocalyptic number.

99999999991867 is a deficient number, since it is larger than the sum of its proper divisors (1).

99999999991867 is an equidigital number, since it uses as much as digits as its factorization.

99999999991867 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1171559558736, while the sum is 112.

The spelling of 99999999991867 in words is "ninety-nine trillion, nine hundred ninety-nine billion, nine hundred ninety-nine million, nine hundred ninety-one thousand, eight hundred sixty-seven".