128229640 has 256 divisors, whose sum is σ = 398131200. Its totient is φ = 35942400.

The previous prime is 128229637. The next prime is 128229641. The reversal of 128229640 is 46922821.

It is a Harshad number since it is a multiple of its sum of digits (34).

It is a junction number, because it is equal to n+sod(n) for n = 128229596 and 128229605.

It is not an unprimeable number, because it can be changed into a prime (128229641) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1623121 + ... + 1623199.

It is an arithmetic number, because the mean of its divisors is an integer number (1555200).

Almost surely, 2^128229640 is an apocalyptic number.

128229640 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 128229640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (199065600).

128229640 is an abundant number, since it is smaller than the sum of its proper divisors (269901560).

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

128229640 is a wasteful number, since it uses less digits than its factorization.

128229640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 156 (or 152 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 34.

The square root of 128229640 is about 11323.8527012674. The cubic root of 128229640 is about 504.2696235182.

The spelling of 128229640 in words is "one hundred twenty-eight million, two hundred twenty-nine thousand, six hundred forty".