128017640 has 32 divisors (see below), whose sum is σ = 288367560. Its totient is φ = 51148800.

The previous prime is 128017639. The next prime is 128017657. The reversal of 128017640 is 46710821.

It can be written as a sum of positive squares in 4 ways, for example, as 105226564 + 22791076 = 10258^2 + 4774^2 .

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 58160 + ... + 60320.

Almost surely, 2^128017640 is an apocalyptic number.

128017640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

128017640 is an abundant number, since it is smaller than the sum of its proper divisors (160349920).

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

128017640 is a wasteful number, since it uses less digits than its factorization.

128017640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3653 (or 3649 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 29.

The square root of 128017640 is about 11314.4880573537. The cubic root of 128017640 is about 503.9915699438.

The spelling of 128017640 in words is "one hundred twenty-eight million, seventeen thousand, six hundred forty".