113221728 has 72 divisors (see below), whose sum is σ = 324540216. Its totient is φ = 37440000.

The previous prime is 113221723. The next prime is 113221781. The reversal of 113221728 is 827122311.

It is a tau number, because it is divible by the number of its divisors (72).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (113221721) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 36228 + ... + 39228.

It is an arithmetic number, because the mean of its divisors is an integer number (4507503).

Almost surely, 2^113221728 is an apocalyptic number.

113221728 is a gapful number since it is divisible by the number (18) 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 113221728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (162270108).

113221728 is an abundant number, since it is smaller than the sum of its proper divisors (211318488).

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

113221728 is a wasteful number, since it uses less digits than its factorization.

113221728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3148 (or 3137 counting only the distinct ones).

The product of its digits is 1344, while the sum is 27.

The square root of 113221728 is about 10640.5699095490. The cubic root of 113221728 is about 483.7748195506.

It can be divided in two parts, 113 and 221728, that added together give a square (221841 = 471²).

The spelling of 113221728 in words is "one hundred thirteen million, two hundred twenty-one thousand, seven hundred twenty-eight".