646481128 has 16 divisors (see below), whose sum is σ = 1229225760. Its totient is φ = 318687600.

The previous prime is 646481123. The next prime is 646481141. The reversal of 646481128 is 821184646.

It is not an unprimeable number, because it can be changed into a prime (646481123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 568518 + ... + 569653.

It is an arithmetic number, because the mean of its divisors is an integer number (76826610).

Almost surely, 2^646481128 is an apocalyptic number.

It is an amenable number.

646481128 is a deficient number, since it is larger than the sum of its proper divisors (582744632).

646481128 is a wasteful number, since it uses less digits than its factorization.

646481128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1138248 (or 1138244 counting only the distinct ones).

The product of its digits is 73728, while the sum is 40.

The square root of 646481128 is about 25425.9931566104. The cubic root of 646481128 is about 864.6731044500.

The spelling of 646481128 in words is "six hundred forty-six million, four hundred eighty-one thousand, one hundred twenty-eight".