66868777628 has 12 divisors (see below), whose sum is σ = 117022197600. Its totient is φ = 33433864032.

The previous prime is 66868777627. The next prime is 66868777639. The reversal of 66868777628 is 82677786866.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66868777627) 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 in 3 ways as a sum of consecutive naturals, for example, 359048 + ... + 512496.

It is an arithmetic number, because the mean of its divisors is an integer number (9751849800).

Almost surely, 2^66868777628 is an apocalyptic number.

It is an amenable number.

66868777628 is a deficient number, since it is larger than the sum of its proper divisors (50153419972).

66868777628 is a wasteful number, since it uses less digits than its factorization.

66868777628 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 262396 (or 262394 counting only the distinct ones).

The product of its digits is 455196672, while the sum is 71.

The spelling of 66868777628 in words is "sixty-six billion, eight hundred sixty-eight million, seven hundred seventy-seven thousand, six hundred twenty-eight".