11328721 has 4 divisors (see below), whose sum is σ = 11456100. Its totient is φ = 11201344.

The previous prime is 11328701. The next prime is 11328743. The reversal of 11328721 is 12782311.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1718721 + 9610000 = 1311^2 + 3100^2 .

It is a cyclic number.

It is not a de Polignac number, because 11328721 - 2⁷ = 11328593 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11328701) 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 3 ways as a sum of consecutive naturals, for example, 63556 + ... + 63733.

It is an arithmetic number, because the mean of its divisors is an integer number (2864025).

Almost surely, 2^11328721 is an apocalyptic number.

It is an amenable number.

11328721 is a deficient number, since it is larger than the sum of its proper divisors (127379).

11328721 is an equidigital number, since it uses as much as digits as its factorization.

11328721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 127378.

The product of its digits is 672, while the sum is 25.

The square root of 11328721 is about 3365.8165428318. The cubic root of 11328721 is about 224.5916610245.

The spelling of 11328721 in words is "eleven million, three hundred twenty-eight thousand, seven hundred twenty-one".