128261172 has 96 divisors (see below), whose sum is σ = 343235200. Its totient is φ = 36951552.

The previous prime is 128261149. The next prime is 128261201. The reversal of 128261172 is 271162821.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 322878 + ... + 323274.

Almost surely, 2^128261172 is an apocalyptic number.

128261172 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 128261172, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (171617600).

128261172 is an abundant number, since it is smaller than the sum of its proper divisors (214974028).

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

128261172 is a wasteful number, since it uses less digits than its factorization.

128261172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 545 (or 543 counting only the distinct ones).

The product of its digits is 2688, while the sum is 30.

The square root of 128261172 is about 11325.2448980143. The cubic root of 128261172 is about 504.3109538653.

The spelling of 128261172 in words is "one hundred twenty-eight million, two hundred sixty-one thousand, one hundred seventy-two".