66777666157 has 2 divisors, whose sum is σ = 66777666158. Its totient is φ = 66777666156.

The previous prime is 66777666143. The next prime is 66777666169. The reversal of 66777666157 is 75166677766.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 66760741161 + 16924996 = 258381^2 + 4114^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66777666157 is a prime.

It is a super-3 number, since 3×66777666157³ (a number of 33 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66777666107) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33388833078 + 33388833079.

It is an arithmetic number, because the mean of its divisors is an integer number (33388833079).

Almost surely, 2^66777666157 is an apocalyptic number.

It is an amenable number.

66777666157 is a deficient number, since it is larger than the sum of its proper divisors (1).

66777666157 is an equidigital number, since it uses as much as digits as its factorization.

66777666157 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 93350880, while the sum is 64.

The spelling of 66777666157 in words is "sixty-six billion, seven hundred seventy-seven million, six hundred sixty-six thousand, one hundred fifty-seven".