168611861729 has 2 divisors, whose sum is σ = 168611861730. Its totient is φ = 168611861728.

The previous prime is 168611861723. The next prime is 168611861773. The reversal of 168611861729 is 927168116861.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 155882832400 + 12729029329 = 394820^2 + 112823^2 .

It is a cyclic number.

It is not a de Polignac number, because 168611861729 - 2³² = 164316894433 is a prime.

It is not a weakly prime, because it can be changed into another prime (168611861723) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 84305930864 + 84305930865.

It is an arithmetic number, because the mean of its divisors is an integer number (84305930865).

Almost surely, 2^168611861729 is an apocalyptic number.

It is an amenable number.

168611861729 is a deficient number, since it is larger than the sum of its proper divisors (1).

168611861729 is an equidigital number, since it uses as much as digits as its factorization.

168611861729 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1741824, while the sum is 56.

The spelling of 168611861729 in words is "one hundred sixty-eight billion, six hundred eleven million, eight hundred sixty-one thousand, seven hundred twenty-nine".