128236840 has 64 divisors (see below), whose sum is σ = 300412800. Its totient is φ = 49206528.

The previous prime is 128236789. The next prime is 128236841. The reversal of 128236840 is 48632821.

It is a junction number, because it is equal to n+sod(n) for n = 128236796 and 128236805.

It is not an unprimeable number, because it can be changed into a prime (128236841) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 263077 + ... + 263563.

It is an arithmetic number, because the mean of its divisors is an integer number (4693950).

Almost surely, 2^128236840 is an apocalyptic number.

128236840 is a gapful number since it is divisible by the number (10) 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 128236840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (150206400).

128236840 is an abundant number, since it is smaller than the sum of its proper divisors (172175960).

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

128236840 is a wasteful number, since it uses less digits than its factorization.

128236840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 754 (or 750 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 34.

The square root of 128236840 is about 11324.1706098063. The cubic root of 128236840 is about 504.2790614644.

The spelling of 128236840 in words is "one hundred twenty-eight million, two hundred thirty-six thousand, eight hundred forty".