66764550436564 has 12 divisors (see below), whose sum is σ = 116989898202100. Its totient is φ = 33338865235968.

The previous prime is 66764550436561. The next prime is 66764550436603. The reversal of 66764550436564 is 46563405546766.

It can be written as a sum of positive squares in 2 ways, for example, as 52276630746564 + 14487919690000 = 7230258^2 + 3806300^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 66764550436564.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66764550436561) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10852492119 + ... + 10852498270.

Almost surely, 2^{66764550436564} is an apocalyptic number.

It is an amenable number.

66764550436564 is a deficient number, since it is larger than the sum of its proper divisors (50225347765536).

66764550436564 is a wasteful number, since it uses less digits than its factorization.

66764550436564 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21704991162 (or 21704991160 counting only the distinct ones).

The product of its (nonzero) digits is 1306368000, while the sum is 67.

The spelling of 66764550436564 in words is "sixty-six trillion, seven hundred sixty-four billion, five hundred fifty million, four hundred thirty-six thousand, five hundred sixty-four".