66660387361 has 2 divisors, whose sum is σ = 66660387362. Its totient is φ = 66660387360.

The previous prime is 66660387349. The next prime is 66660387371. The reversal of 66660387361 is 16378306666.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 66270719761 + 389667600 = 257431^2 + 19740^2 .

It is a cyclic number.

It is not a de Polignac number, because 66660387361 - 2²⁹ = 66123516449 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 66660387299 and 66660387308.

It is not a weakly prime, because it can be changed into another prime (66660387371) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33330193680 + 33330193681.

It is an arithmetic number, because the mean of its divisors is an integer number (33330193681).

Almost surely, 2^66660387361 is an apocalyptic number.

It is an amenable number.

66660387361 is a deficient number, since it is larger than the sum of its proper divisors (1).

66660387361 is an equidigital number, since it uses as much as digits as its factorization.

66660387361 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3919104, while the sum is 52.

The spelling of 66660387361 in words is "sixty-six billion, six hundred sixty million, three hundred eighty-seven thousand, three hundred sixty-one".