128403668 has 6 divisors (see below), whose sum is σ = 224706426. Its totient is φ = 64201832.

The previous prime is 128403659. The next prime is 128403679. The reversal of 128403668 is 866304821.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 102981904 + 25421764 = 10148^2 + 5042^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16050455 + ... + 16050462.

It is an arithmetic number, because the mean of its divisors is an integer number (37451071).

Almost surely, 2^128403668 is an apocalyptic number.

It is an amenable number.

128403668 is a deficient number, since it is larger than the sum of its proper divisors (96302758).

128403668 is a wasteful number, since it uses less digits than its factorization.

128403668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32100921 (or 32100919 counting only the distinct ones).

The product of its (nonzero) digits is 55296, while the sum is 38.

The square root of 128403668 is about 11331.5342297502. The cubic root of 128403668 is about 504.4976450683.

The spelling of 128403668 in words is "one hundred twenty-eight million, four hundred three thousand, six hundred sixty-eight".