66430777556 has 36 divisors (see below), whose sum is σ = 137328405984. Its totient is φ = 27873050400.

The previous prime is 66430777507. The next prime is 66430777631. The reversal of 66430777556 is 65577703466.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4459400 + ... + 4474271.

It is an arithmetic number, because the mean of its divisors is an integer number (3814677944).

Almost surely, 2^66430777556 is an apocalyptic number.

It is an amenable number.

66430777556 is an abundant number, since it is smaller than the sum of its proper divisors (70897628428).

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

66430777556 is a wasteful number, since it uses less digits than its factorization.

66430777556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8933712 (or 8933697 counting only the distinct ones).

The product of its (nonzero) digits is 22226400, while the sum is 56.

The spelling of 66430777556 in words is "sixty-six billion, four hundred thirty million, seven hundred seventy-seven thousand, five hundred fifty-six".