66556443660 has 96 divisors (see below), whose sum is σ = 222240678912. Its totient is φ = 14551468800.

The previous prime is 66556443647. The next prime is 66556443671. The reversal of 66556443660 is 6634465566.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3435291 + ... + 3454610.

It is an arithmetic number, because the mean of its divisors is an integer number (2315007072).

Almost surely, 2^66556443660 is an apocalyptic number.

66556443660 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

66556443660 is an abundant number, since it is smaller than the sum of its proper divisors (155684235252).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66556443660 is a wasteful number, since it uses less digits than its factorization.

66556443660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6889943 (or 6889941 counting only the distinct ones).

The product of its (nonzero) digits is 9331200, while the sum is 51.

The spelling of 66556443660 in words is "sixty-six billion, five hundred fifty-six million, four hundred forty-three thousand, six hundred sixty".