168611861777 has 2 divisors, whose sum is σ = 168611861778. Its totient is φ = 168611861776.

The previous prime is 168611861773. The next prime is 168611861779. The reversal of 168611861777 is 777168116861.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 157018817536 + 11593044241 = 396256^2 + 107671^2 .

It is a cyclic number.

It is not a de Polignac number, because 168611861777 - 2² = 168611861773 is a prime.

Together with 168611861779, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (168611861773) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 84305930888 + 84305930889.

It is an arithmetic number, because the mean of its divisors is an integer number (84305930889).

Almost surely, 2^168611861777 is an apocalyptic number.

It is an amenable number.

168611861777 is a deficient number, since it is larger than the sum of its proper divisors (1).

168611861777 is an equidigital number, since it uses as much as digits as its factorization.

168611861777 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4741632, while the sum is 59.

The spelling of 168611861777 in words is "one hundred sixty-eight billion, six hundred eleven million, eight hundred sixty-one thousand, seven hundred seventy-seven".