128921472 has 192 divisors, whose sum is σ = 408142800. Its totient is φ = 38879232.

The previous prime is 128921453. The next prime is 128921477. The reversal of 128921472 is 274129821.

It is a tau number, because it is divible by the number of its divisors (192).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128921477) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 567823 + ... + 568049.

Almost surely, 2^128921472 is an apocalyptic number.

128921472 is a gapful number since it is divisible by the number (12) 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 128921472, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (204071400).

128921472 is an abundant number, since it is smaller than the sum of its proper divisors (279221328).

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

128921472 is a wasteful number, since it uses less digits than its factorization.

128921472 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 293 (or 278 counting only the distinct ones).

The product of its digits is 16128, while the sum is 36.

The square root of 128921472 is about 11354.3591628942. The cubic root of 128921472 is about 505.1748856758.

It can be divided in two parts, 128 and 921472, that added together give a square (921600 = 960²).

The spelling of 128921472 in words is "one hundred twenty-eight million, nine hundred twenty-one thousand, four hundred seventy-two".