8782166461781 has 2 divisors, whose sum is σ = 8782166461782. Its totient is φ = 8782166461780.

The previous prime is 8782166461769. The next prime is 8782166461787. The reversal of 8782166461781 is 1871646612878.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 7804508259025 + 977658202756 = 2793655^2 + 988766^2 .

It is a cyclic number.

It is not a de Polignac number, because 8782166461781 - 2¹⁸ = 8782166199637 is a prime.

It is a super-2 number, since 2×8782166461781² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8782166461787) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4391083230890 + 4391083230891.

It is an arithmetic number, because the mean of its divisors is an integer number (4391083230891).

Almost surely, 2^{8782166461781} is an apocalyptic number.

It is an amenable number.

8782166461781 is a deficient number, since it is larger than the sum of its proper divisors (1).

8782166461781 is an equidigital number, since it uses as much as digits as its factorization.

8782166461781 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 43352064, while the sum is 65.

The spelling of 8782166461781 in words is "eight trillion, seven hundred eighty-two billion, one hundred sixty-six million, four hundred sixty-one thousand, seven hundred eighty-one".