81835168999 has 2 divisors, whose sum is σ = 81835169000. Its totient is φ = 81835168998.

The previous prime is 81835168957. The next prime is 81835169051. The reversal of 81835168999 is 99986153818.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 81835168999 - 2⁹ = 81835168487 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81835168399) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40917584499 + 40917584500.

It is an arithmetic number, because the mean of its divisors is an integer number (40917584500).

Almost surely, 2^81835168999 is an apocalyptic number.

81835168999 is a deficient number, since it is larger than the sum of its proper divisors (1).

81835168999 is an equidigital number, since it uses as much as digits as its factorization.

81835168999 is an evil number, because the sum of its binary digits is even.

The product of its digits is 33592320, while the sum is 67.

The spelling of 81835168999 in words is "eighty-one billion, eight hundred thirty-five million, one hundred sixty-eight thousand, nine hundred ninety-nine".