128381403906 has 24 divisors (see below), whose sum is σ = 317896809984. Its totient is φ = 36680401080.

The previous prime is 128381403893. The next prime is 128381403907. The reversal of 128381403906 is 609304183821.

128381403906 is a `hidden beast` number, since 1 + 2 + 83 + 81 + 403 + 90 + 6 = 666.

It is not an unprimeable number, because it can be changed into a prime (128381403907) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 509449890 + ... + 509450141.

It is an arithmetic number, because the mean of its divisors is an integer number (13245700416).

Almost surely, 2^128381403906 is an apocalyptic number.

128381403906 is an abundant number, since it is smaller than the sum of its proper divisors (189515406078).

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

128381403906 is a wasteful number, since it uses less digits than its factorization.

128381403906 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1018900046 (or 1018900043 counting only the distinct ones).

The product of its (nonzero) digits is 248832, while the sum is 45.

The spelling of 128381403906 in words is "one hundred twenty-eight billion, three hundred eighty-one million, four hundred three thousand, nine hundred six".