66775057767 has 24 divisors (see below), whose sum is σ = 108065128080. Its totient is φ = 39375953280.

The previous prime is 66775057759. The next prime is 66775057777. The reversal of 66775057767 is 76775057766.

66775057767 is a `hidden beast` number, since 6 + 6 + 7 + 7 + 50 + 577 + 6 + 7 = 666.

66775057767 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 66775057767 - 2³ = 66775057759 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66775057777) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9111142 + ... + 9118467.

It is an arithmetic number, because the mean of its divisors is an integer number (4502713670).

Almost surely, 2^66775057767 is an apocalyptic number.

66775057767 is a deficient number, since it is larger than the sum of its proper divisors (41290070313).

66775057767 is a wasteful number, since it uses less digits than its factorization.

66775057767 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18229663 (or 18229660 counting only the distinct ones).

The product of its (nonzero) digits is 90757800, while the sum is 63.

Subtracting 66775057767 from its reverse (76775057766), we obtain a palindrome (9999999999).

The spelling of 66775057767 in words is "sixty-six billion, seven hundred seventy-five million, fifty-seven thousand, seven hundred sixty-seven".