218681779379471 has 2 divisors, whose sum is σ = 218681779379472. Its totient is φ = 218681779379470.

The previous prime is 218681779379447. The next prime is 218681779379477. The reversal of 218681779379471 is 174973977186812.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-218681779379471 is a prime.

It is a super-3 number, since 3×218681779379471³ (a number of 44 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (218681779379477) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 109340889689735 + 109340889689736.

It is an arithmetic number, because the mean of its divisors is an integer number (109340889689736).

Almost surely, 2^{218681779379471} is an apocalyptic number.

218681779379471 is a deficient number, since it is larger than the sum of its proper divisors (1).

218681779379471 is an equidigital number, since it uses as much as digits as its factorization.

218681779379471 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1792336896, while the sum is 80.

The spelling of 218681779379471 in words is "two hundred eighteen trillion, six hundred eighty-one billion, seven hundred seventy-nine million, three hundred seventy-nine thousand, four hundred seventy-one".