128681664 has 28 divisors (see below), whose sum is σ = 340470744. Its totient is φ = 42893824.

The previous prime is 128681659. The next prime is 128681669. The reversal of 128681664 is 466186821.

It is an interprime number because it is at equal distance from previous prime (128681659) and next prime (128681669).

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (128681669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 334917 + ... + 335300.

Almost surely, 2^128681664 is an apocalyptic number.

It is an amenable number.

128681664 is an abundant number, since it is smaller than the sum of its proper divisors (211789080).

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

128681664 is an equidigital number, since it uses as much as digits as its factorization.

128681664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 670232 (or 670222 counting only the distinct ones).

The product of its digits is 110592, while the sum is 42.

The square root of 128681664 is about 11343.7940742945. The cubic root of 128681664 is about 504.8614644664.

The spelling of 128681664 in words is "one hundred twenty-eight million, six hundred eighty-one thousand, six hundred sixty-four".