128581936 has 40 divisors (see below), whose sum is σ = 286640384. Its totient is φ = 54734400.

The previous prime is 128581927. The next prime is 128581951. The reversal of 128581936 is 639185821.

It is a junction number, because it is equal to n+sod(n) for n = 128581892 and 128581901.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13111 + ... + 20713.

Almost surely, 2^128581936 is an apocalyptic number.

128581936 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 128581936, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (143320192).

128581936 is an abundant number, since it is smaller than the sum of its proper divisors (158058448).

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

128581936 is a wasteful number, since it uses less digits than its factorization.

128581936 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7769 (or 7763 counting only the distinct ones).

The product of its digits is 103680, while the sum is 43.

The square root of 128581936 is about 11339.3975148594. The cubic root of 128581936 is about 504.7310085933.

The spelling of 128581936 in words is "one hundred twenty-eight million, five hundred eighty-one thousand, nine hundred thirty-six".