128401280 has 64 divisors (see below), whose sum is σ = 350822880. Its totient is φ = 44021760.

The previous prime is 128401277. The next prime is 128401283. The reversal of 128401280 is 82104821.

It is an interprime number because it is at equal distance from previous prime (128401277) and next prime (128401283).

It is a tau number, because it is divible by the number of its divisors (64).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128401283) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9851 + ... + 18810.

Almost surely, 2^128401280 is an apocalyptic number.

128401280 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

128401280 is an abundant number, since it is smaller than the sum of its proper divisors (222421600).

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

128401280 is an equidigital number, since it uses as much as digits as its factorization.

128401280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28687 (or 28675 counting only the distinct ones).

The product of its (nonzero) digits is 1024, while the sum is 26.

The square root of 128401280 is about 11331.4288595922. The cubic root of 128401280 is about 504.4945175672.

The spelling of 128401280 in words is "one hundred twenty-eight million, four hundred one thousand, two hundred eighty".