66657716612 has 24 divisors (see below), whose sum is σ = 118822810680. Its totient is φ = 32713809920.

The previous prime is 66657716611. The next prime is 66657716617. The reversal of 66657716612 is 21661775666.

It can be written as a sum of positive squares in 4 ways, for example, as 13145998336 + 53511718276 = 114656^2 + 231326^2 .

It is not an unprimeable number, because it can be changed into a prime (66657716611) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 634589 + ... + 732132.

It is an arithmetic number, because the mean of its divisors is an integer number (4950950445).

Almost surely, 2^66657716612 is an apocalyptic number.

It is an amenable number.

66657716612 is a deficient number, since it is larger than the sum of its proper divisors (52165094068).

66657716612 is a wasteful number, since it uses less digits than its factorization.

66657716612 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1366951 (or 1366949 counting only the distinct ones).

The product of its digits is 3810240, while the sum is 53.

It can be divided in two parts, 6665 and 7716612, that added together give a palindrome (7723277).

The spelling of 66657716612 in words is "sixty-six billion, six hundred fifty-seven million, seven hundred sixteen thousand, six hundred twelve".