11521728 has 84 divisors (see below), whose sum is σ = 33561528. Its totient is φ = 3778560.

The previous prime is 11521717. The next prime is 11521747. The reversal of 11521728 is 82712511.

It is a super-2 number, since 2×11521728² = 265500432211968, which contains 22 as substring.

11521728 is a modest number, since divided by 1728 gives 1152 as remainder.

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 11 ways as a sum of consecutive naturals, for example, 47688 + ... + 47928.

It is an arithmetic number, because the mean of its divisors is an integer number (399542).

Almost surely, 2^11521728 is an apocalyptic number.

11521728 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 11521728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (16780764).

11521728 is an abundant number, since it is smaller than the sum of its proper divisors (22039800).

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

11521728 is a wasteful number, since it uses less digits than its factorization.

11521728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 342 (or 329 counting only the distinct ones).

The product of its digits is 1120, while the sum is 27.

The square root of 11521728 is about 3394.3670985914. The cubic root of 11521728 is about 225.8599387992.

The spelling of 11521728 in words is "eleven million, five hundred twenty-one thousand, seven hundred twenty-eight".