128581398 has 64 divisors (see below), whose sum is σ = 328147200. Its totient is φ = 36910080.

The previous prime is 128581393. The next prime is 128581403. The reversal of 128581398 is 893185821.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (128581393) and next prime (128581403).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128581393) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5590 + ... + 16982.

It is an arithmetic number, because the mean of its divisors is an integer number (5127300).

Almost surely, 2^128581398 is an apocalyptic number.

128581398 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 128581398, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (164073600).

128581398 is an abundant number, since it is smaller than the sum of its proper divisors (199565802).

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

128581398 is a wasteful number, since it uses less digits than its factorization.

128581398 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11434 (or 11428 counting only the distinct ones).

The product of its digits is 138240, while the sum is 45.

The square root of 128581398 is about 11339.3737922339. The cubic root of 128581398 is about 504.7303046436.

The spelling of 128581398 in words is "one hundred twenty-eight million, five hundred eighty-one thousand, three hundred ninety-eight".