66128547256 has 64 divisors (see below), whose sum is σ = 127599436800. Its totient is φ = 32111468928.

The previous prime is 66128547211. The next prime is 66128547259. The reversal of 66128547256 is 65274582166.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66128547259) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 59952801 + ... + 59953903.

It is an arithmetic number, because the mean of its divisors is an integer number (1993741200).

Almost surely, 2^66128547256 is an apocalyptic number.

It is an amenable number.

66128547256 is a deficient number, since it is larger than the sum of its proper divisors (61470889544).

66128547256 is a wasteful number, since it uses less digits than its factorization.

66128547256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1988 (or 1984 counting only the distinct ones).

The product of its digits is 4838400, while the sum is 52.

The spelling of 66128547256 in words is "sixty-six billion, one hundred twenty-eight million, five hundred forty-seven thousand, two hundred fifty-six".