128641408 has 32 divisors (see below), whose sum is σ = 292890960. Its totient is φ = 55131648.

The previous prime is 128641367. The next prime is 128641433. The reversal of 128641408 is 804146821.

It is a tau number, because it is divible by the number of its divisors (32).

It is a super-2 number, since 2×128641408² = 33097223704444928, which contains 22 as substring.

It is a congruent number.

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 3 ways as a sum of consecutive naturals, for example, 70891 + ... + 72682.

Almost surely, 2^128641408 is an apocalyptic number.

It is an amenable number.

128641408 is an abundant number, since it is smaller than the sum of its proper divisors (164249552).

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

128641408 is an equidigital number, since it uses as much as digits as its factorization.

128641408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 143594 (or 143582 counting only the distinct ones).

The product of its (nonzero) digits is 12288, while the sum is 34.

The square root of 128641408 is about 11342.0195732506. The cubic root of 128641408 is about 504.8088130314.

The spelling of 128641408 in words is "one hundred twenty-eight million, six hundred forty-one thousand, four hundred eight".