11521813 has 2 divisors, whose sum is σ = 11521814. Its totient is φ = 11521812.

The previous prime is 11521799. The next prime is 11521817. The reversal of 11521813 is 31812511.

11521813 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6036849 + 5484964 = 2457^2 + 2342^2 .

It is a cyclic number.

It is not a de Polignac number, because 11521813 - 2¹⁷ = 11390741 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11521817) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5760906 + 5760907.

It is an arithmetic number, because the mean of its divisors is an integer number (5760907).

Almost surely, 2^11521813 is an apocalyptic number.

It is an amenable number.

11521813 is a deficient number, since it is larger than the sum of its proper divisors (1).

11521813 is an equidigital number, since it uses as much as digits as its factorization.

11521813 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 240, while the sum is 22.

The square root of 11521813 is about 3394.3796193119. The cubic root of 11521813 is about 225.8604942150.

It can be divided in two parts, 1152181 and 3, that multiplied together give a palindrome (3456543).

The spelling of 11521813 in words is "eleven million, five hundred twenty-one thousand, eight hundred thirteen".