166431234348961 has 2 divisors, whose sum is σ = 166431234348962. Its totient is φ = 166431234348960.

The previous prime is 166431234348959. The next prime is 166431234348979. The reversal of 166431234348961 is 169843432134661.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 162676785579361 + 3754448769600 = 12754481^2 + 1937640^2 .

It is a cyclic number.

It is not a de Polignac number, because 166431234348961 - 2¹ = 166431234348959 is a prime.

Together with 166431234348959, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 166431234348961.

It is not a weakly prime, because it can be changed into another prime (166431234348661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83215617174480 + 83215617174481.

It is an arithmetic number, because the mean of its divisors is an integer number (83215617174481).

Almost surely, 2^{166431234348961} is an apocalyptic number.

It is an amenable number.

166431234348961 is a deficient number, since it is larger than the sum of its proper divisors (1).

166431234348961 is an equidigital number, since it uses as much as digits as its factorization.

166431234348961 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 53747712, while the sum is 61.

The spelling of 166431234348961 in words is "one hundred sixty-six trillion, four hundred thirty-one billion, two hundred thirty-four million, three hundred forty-eight thousand, nine hundred sixty-one".