8064666781 has 2 divisors, whose sum is σ = 8064666782. Its totient is φ = 8064666780.

The previous prime is 8064666773. The next prime is 8064666791. The reversal of 8064666781 is 1876664608.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6749444025 + 1315222756 = 82155^2 + 36266^2 .

It is a cyclic number.

It is not a de Polignac number, because 8064666781 - 2³ = 8064666773 is a prime.

It is a super-2 number, since 2×8064666781² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8064666791) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4032333390 + 4032333391.

It is an arithmetic number, because the mean of its divisors is an integer number (4032333391).

Almost surely, 2^8064666781 is an apocalyptic number.

It is an amenable number.

8064666781 is a deficient number, since it is larger than the sum of its proper divisors (1).

8064666781 is an equidigital number, since it uses as much as digits as its factorization.

8064666781 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2322432, while the sum is 52.

The square root of 8064666781 is about 89803.4898041273. The cubic root of 8064666781 is about 2005.3744431605.

The spelling of 8064666781 in words is "eight billion, sixty-four million, six hundred sixty-six thousand, seven hundred eighty-one".