12784513805669 has 2 divisors, whose sum is σ = 12784513805670. Its totient is φ = 12784513805668.

The previous prime is 12784513805639. The next prime is 12784513805683. The reversal of 12784513805669 is 96650831548721.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9841007413444 + 2943506392225 = 3137038^2 + 1715665^2 .

It is a cyclic number.

It is not a de Polignac number, because 12784513805669 - 2¹⁶ = 12784513740133 is a prime.

It is a super-2 number, since 2×12784513805669² (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 (12784513805639) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6392256902834 + 6392256902835.

It is an arithmetic number, because the mean of its divisors is an integer number (6392256902835).

It is a 1-persistent number, because it is pandigital, but 2⋅12784513805669 = 25569027611338 is not.

Almost surely, 2^{12784513805669} is an apocalyptic number.

It is an amenable number.

12784513805669 is a deficient number, since it is larger than the sum of its proper divisors (1).

12784513805669 is an equidigital number, since it uses as much as digits as its factorization.

12784513805669 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 87091200, while the sum is 65.

The spelling of 12784513805669 in words is "twelve trillion, seven hundred eighty-four billion, five hundred thirteen million, eight hundred five thousand, six hundred sixty-nine".