66855043313 has 2 divisors, whose sum is σ = 66855043314. Its totient is φ = 66855043312.

The previous prime is 66855043271. The next prime is 66855043327. The reversal of 66855043313 is 31334055866.

It is a happy number.

66855043313 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 33893914609 + 32961128704 = 184103^2 + 181552^2 .

It is a cyclic number.

It is not a de Polignac number, because 66855043313 - 2¹² = 66855039217 is a prime.

It is not a weakly prime, because it can be changed into another prime (66855043363) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33427521656 + 33427521657.

It is an arithmetic number, because the mean of its divisors is an integer number (33427521657).

Almost surely, 2^66855043313 is an apocalyptic number.

It is an amenable number.

66855043313 is a deficient number, since it is larger than the sum of its proper divisors (1).

66855043313 is an equidigital number, since it uses as much as digits as its factorization.

66855043313 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 777600, while the sum is 44.

The spelling of 66855043313 in words is "sixty-six billion, eight hundred fifty-five million, forty-three thousand, three hundred thirteen".