66739510657 has 2 divisors, whose sum is σ = 66739510658. Its totient is φ = 66739510656.

The previous prime is 66739510631. The next prime is 66739510687. The reversal of 66739510657 is 75601593766.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 58025101456 + 8714409201 = 240884^2 + 93351^2 .

It is a cyclic number.

It is not a de Polignac number, because 66739510657 - 2³⁵ = 32379772289 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 66739510598 and 66739510607.

It is not a weakly prime, because it can be changed into another prime (66739510687) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33369755328 + 33369755329.

It is an arithmetic number, because the mean of its divisors is an integer number (33369755329).

Almost surely, 2^66739510657 is an apocalyptic number.

It is an amenable number.

66739510657 is a deficient number, since it is larger than the sum of its proper divisors (1).

66739510657 is an equidigital number, since it uses as much as digits as its factorization.

66739510657 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7144200, while the sum is 55.

The spelling of 66739510657 in words is "sixty-six billion, seven hundred thirty-nine million, five hundred ten thousand, six hundred fifty-seven".