72784160966681 has 2 divisors, whose sum is σ = 72784160966682. Its totient is φ = 72784160966680.

The previous prime is 72784160966659. The next prime is 72784160966717. The reversal of 72784160966681 is 18666906148727.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 38948021497225 + 33836139469456 = 6240835^2 + 5816884^2 .

It is an emirp because it is prime and its reverse (18666906148727) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 72784160966681 - 2¹⁰ = 72784160965657 is a prime.

It is a super-2 number, since 2×72784160966681² (a number of 29 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (72784160966611) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36392080483340 + 36392080483341.

It is an arithmetic number, because the mean of its divisors is an integer number (36392080483341).

Almost surely, 2^{72784160966681} is an apocalyptic number.

It is an amenable number.

72784160966681 is a deficient number, since it is larger than the sum of its proper divisors (1).

72784160966681 is an equidigital number, since it uses as much as digits as its factorization.

72784160966681 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 292626432, while the sum is 71.

The spelling of 72784160966681 in words is "seventy-two trillion, seven hundred eighty-four billion, one hundred sixty million, nine hundred sixty-six thousand, six hundred eighty-one".