128564250 has 128 divisors (see below), whose sum is σ = 347742720. Its totient is φ = 31539200.

The previous prime is 128564243. The next prime is 128564257. The reversal of 128564250 is 52465821.

It is an interprime number because it is at equal distance from previous prime (128564243) and next prime (128564257).

It is not an unprimeable number, because it can be changed into a prime (128564257) 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, 500122 + ... + 500378.

It is an arithmetic number, because the mean of its divisors is an integer number (2716740).

Almost surely, 2^128564250 is an apocalyptic number.

128564250 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 128564250, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (173871360).

128564250 is an abundant number, since it is smaller than the sum of its proper divisors (219178470).

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

128564250 is a wasteful number, since it uses less digits than its factorization.

128564250 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 329 (or 319 counting only the distinct ones).

The product of its (nonzero) digits is 19200, while the sum is 33.

The square root of 128564250 is about 11338.6176406121. The cubic root of 128564250 is about 504.7078661982.

The spelling of 128564250 in words is "one hundred twenty-eight million, five hundred sixty-four thousand, two hundred fifty".