66618757 has 2 divisors, whose sum is σ = 66618758. Its totient is φ = 66618756.

The previous prime is 66618751. The next prime is 66618781. The reversal of 66618757 is 75781666.

66618757 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 57851236 + 8767521 = 7606^2 + 2961^2 .

It is a cyclic number.

It is not a de Polignac number, because 66618757 - 2³ = 66618749 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66618751) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33309378 + 33309379.

It is an arithmetic number, because the mean of its divisors is an integer number (33309379).

Almost surely, 2^66618757 is an apocalyptic number.

It is an amenable number.

66618757 is a deficient number, since it is larger than the sum of its proper divisors (1).

66618757 is an equidigital number, since it uses as much as digits as its factorization.

66618757 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 423360, while the sum is 46.

The square root of 66618757 is about 8162.0314260605. The cubic root of 66618757 is about 405.3829776710.

The spelling of 66618757 in words is "sixty-six million, six hundred eighteen thousand, seven hundred fifty-seven".