2161688364617 has 2 divisors, whose sum is σ = 2161688364618. Its totient is φ = 2161688364616.

The previous prime is 2161688364613. The next prime is 2161688364623. The reversal of 2161688364617 is 7164638861612.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1115683075081 + 1046005289536 = 1056259^2 + 1022744^2 .

It is a cyclic number.

It is not a de Polignac number, because 2161688364617 - 2² = 2161688364613 is a prime.

It is not a weakly prime, because it can be changed into another prime (2161688364611) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1080844182308 + 1080844182309.

It is an arithmetic number, because the mean of its divisors is an integer number (1080844182309).

Almost surely, 2^{2161688364617} is an apocalyptic number.

It is an amenable number.

2161688364617 is a deficient number, since it is larger than the sum of its proper divisors (1).

2161688364617 is an equidigital number, since it uses as much as digits as its factorization.

2161688364617 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 13934592, while the sum is 59.

The spelling of 2161688364617 in words is "two trillion, one hundred sixty-one billion, six hundred eighty-eight million, three hundred sixty-four thousand, six hundred seventeen".