11310821 has 4 divisors (see below), whose sum is σ = 11414700. Its totient is φ = 11206944.

The previous prime is 11310809. The next prime is 11310823. The reversal of 11310821 is 12801311.

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 9541921 + 1768900 = 3089^2 + 1330^2 .

It is not a de Polignac number, because 11310821 - 2¹⁸ = 11048677 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 11310821.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11310823) 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, 51776 + ... + 51993.

It is an arithmetic number, because the mean of its divisors is an integer number (2853675).

Almost surely, 2^11310821 is an apocalyptic number.

It is an amenable number.

11310821 is a deficient number, since it is larger than the sum of its proper divisors (103879).

11310821 is a wasteful number, since it uses less digits than its factorization.

11310821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 103878.

The product of its (nonzero) digits is 48, while the sum is 17.

The square root of 11310821 is about 3363.1564043321. The cubic root of 11310821 is about 224.4733096247.

The spelling of 11310821 in words is "eleven million, three hundred ten thousand, eight hundred twenty-one".