11819581 has 2 divisors, whose sum is σ = 11819582. Its totient is φ = 11819580.

The previous prime is 11819567. The next prime is 11819593. The reversal of 11819581 is 18591811.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11792356 + 27225 = 3434^2 + 165^2 .

It is a cyclic number.

It is not a de Polignac number, because 11819581 - 2⁹ = 11819069 is a prime.

It is a super-2 number, since 2×11819581² = 279404990031122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11819531) 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 as a sum of consecutive naturals, namely, 5909790 + 5909791.

It is an arithmetic number, because the mean of its divisors is an integer number (5909791).

Almost surely, 2^11819581 is an apocalyptic number.

It is an amenable number.

11819581 is a deficient number, since it is larger than the sum of its proper divisors (1).

11819581 is an equidigital number, since it uses as much as digits as its factorization.

11819581 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2880, while the sum is 34.

The square root of 11819581 is about 3437.9617508053. The cubic root of 11819581 is about 227.7896708620.

The spelling of 11819581 in words is "eleven million, eight hundred nineteen thousand, five hundred eighty-one".