11808521 has 2 divisors, whose sum is σ = 11808522. Its totient is φ = 11808520.

The previous prime is 11808509. The next prime is 11808547. The reversal of 11808521 is 12580811.

It is an a-pointer prime, because the next prime (11808547) can be obtained adding 11808521 to its sum of digits (26).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 9834496 + 1974025 = 3136^2 + 1405^2 .

It is a cyclic number.

It is not a de Polignac number, because 11808521 - 2¹⁸ = 11546377 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (11808571) 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 as a sum of consecutive naturals, namely, 5904260 + 5904261.

It is an arithmetic number, because the mean of its divisors is an integer number (5904261).

Almost surely, 2^11808521 is an apocalyptic number.

It is an amenable number.

11808521 is a deficient number, since it is larger than the sum of its proper divisors (1).

11808521 is an equidigital number, since it uses as much as digits as its factorization.

11808521 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 640, while the sum is 26.

The square root of 11808521 is about 3436.3528631385. The cubic root of 11808521 is about 227.7185984051.

The spelling of 11808521 in words is "eleven million, eight hundred eight thousand, five hundred twenty-one".