128581384 has 8 divisors (see below), whose sum is σ = 241090110. Its totient is φ = 64290688.

The previous prime is 128581381. The next prime is 128581393. The reversal of 128581384 is 483185821.

It can be written as a sum of positive squares in only one way, i.e., 105637284 + 22944100 = 10278^2 + 4790^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-2 number, since 2×128581384² = 33066344622710912, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (128581381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8036329 + ... + 8036344.

Almost surely, 2^128581384 is an apocalyptic number.

It is an amenable number.

128581384 is a deficient number, since it is larger than the sum of its proper divisors (112508726).

128581384 is a wasteful number, since it uses less digits than its factorization.

128581384 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16072679 (or 16072675 counting only the distinct ones).

The product of its digits is 61440, while the sum is 40.

The square root of 128581384 is about 11339.3731749158. The cubic root of 128581384 is about 504.7302863252.

The spelling of 128581384 in words is "one hundred twenty-eight million, five hundred eighty-one thousand, three hundred eighty-four".