166021564202869 has 2 divisors, whose sum is σ = 166021564202870. Its totient is φ = 166021564202868.

The previous prime is 166021564202849. The next prime is 166021564202957. The reversal of 166021564202869 is 968202465120661.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 138633245644644 + 27388318558225 = 11774262^2 + 5233385^2 .

It is a cyclic number.

It is not a de Polignac number, because 166021564202869 - 2¹³ = 166021564194677 is a prime.

It is a super-3 number, since 3×166021564202869³ (a number of 44 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (166021564202849) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83010782101434 + 83010782101435.

It is an arithmetic number, because the mean of its divisors is an integer number (83010782101435).

Almost surely, 2^{166021564202869} is an apocalyptic number.

It is an amenable number.

166021564202869 is a deficient number, since it is larger than the sum of its proper divisors (1).

166021564202869 is an equidigital number, since it uses as much as digits as its factorization.

166021564202869 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 14929920, while the sum is 58.

The spelling of 166021564202869 in words is "one hundred sixty-six trillion, twenty-one billion, five hundred sixty-four million, two hundred two thousand, eight hundred sixty-nine".