11415721 has 8 divisors (see below), whose sum is σ = 12414600. Its totient is φ = 10453248.

The previous prime is 11415709. The next prime is 11415739. The reversal of 11415721 is 12751411.

It can be written as a sum of positive squares in 4 ways, for example, as 4260096 + 7155625 = 2064^2 + 2675^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 11415721 - 2¹⁷ = 11284649 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 11415692 and 11415701.

It is not an unprimeable number, because it can be changed into a prime (11415791) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8446 + ... + 9703.

It is an arithmetic number, because the mean of its divisors is an integer number (1551825).

Almost surely, 2^11415721 is an apocalyptic number.

It is an amenable number.

11415721 is a deficient number, since it is larger than the sum of its proper divisors (998879).

11415721 is a wasteful number, since it uses less digits than its factorization.

11415721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18203.

The product of its digits is 280, while the sum is 22.

The square root of 11415721 is about 3378.7158803309. The cubic root of 11415721 is about 225.1651199466.

The spelling of 11415721 in words is "eleven million, four hundred fifteen thousand, seven hundred twenty-one".