166531322899 has 2 divisors, whose sum is σ = 166531322900. Its totient is φ = 166531322898.

The previous prime is 166531322887. The next prime is 166531322989. The reversal of 166531322899 is 998223135661.

Together with next prime (166531322989) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-166531322899 is a prime.

It is not a weakly prime, because it can be changed into another prime (166531322099) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83265661449 + 83265661450.

It is an arithmetic number, because the mean of its divisors is an integer number (83265661450).

Almost surely, 2^166531322899 is an apocalyptic number.

166531322899 is a deficient number, since it is larger than the sum of its proper divisors (1).

166531322899 is an equidigital number, since it uses as much as digits as its factorization.

166531322899 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4199040, while the sum is 55.

The spelling of 166531322899 in words is "one hundred sixty-six billion, five hundred thirty-one million, three hundred twenty-two thousand, eight hundred ninety-nine".