128005920 has 480 divisors, whose sum is σ = 553246848. Its totient is φ = 27205632.

The previous prime is 128005873. The next prime is 128005921. The reversal of 128005920 is 29500821.

It is a tau number, because it is divible by the number of its divisors (480).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (128005921) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 1542199 + ... + 1542281.

Almost surely, 2^128005920 is an apocalyptic number.

128005920 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 128005920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (276623424).

128005920 is an abundant number, since it is smaller than the sum of its proper divisors (425240928).

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

128005920 is a wasteful number, since it uses less digits than its factorization.

128005920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 134 (or 117 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 27.

The square root of 128005920 is about 11313.9701254688. The cubic root of 128005920 is about 503.9761893513.

The spelling of 128005920 in words is "one hundred twenty-eight million, five thousand, nine hundred twenty".