128387668 has 6 divisors (see below), whose sum is σ = 224678426. Its totient is φ = 64193832.

The previous prime is 128387663. The next prime is 128387671. The reversal of 128387668 is 866783821.

It can be written as a sum of positive squares in only one way, i.e., 98049604 + 30338064 = 9902^2 + 5508^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128387663) 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 as a sum of consecutive naturals, namely, 16048455 + ... + 16048462.

Almost surely, 2^128387668 is an apocalyptic number.

It is an amenable number.

128387668 is a deficient number, since it is larger than the sum of its proper divisors (96290758).

128387668 is a wasteful number, since it uses less digits than its factorization.

128387668 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32096921 (or 32096919 counting only the distinct ones).

The product of its digits is 774144, while the sum is 49.

The square root of 128387668 is about 11330.8282133302. The cubic root of 128387668 is about 504.4766895465.

The spelling of 128387668 in words is "one hundred twenty-eight million, three hundred eighty-seven thousand, six hundred sixty-eight".