11821081 has 2 divisors, whose sum is σ = 11821082. Its totient is φ = 11821080.

The previous prime is 11821031. The next prime is 11821123. The reversal of 11821081 is 18012811.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 7241481 + 4579600 = 2691^2 + 2140^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11821081 is a prime.

It is a super-2 number, since 2×11821081² = 279475912017122, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (11821031) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5910540 + 5910541.

It is an arithmetic number, because the mean of its divisors is an integer number (5910541).

Almost surely, 2^11821081 is an apocalyptic number.

It is an amenable number.

11821081 is a deficient number, since it is larger than the sum of its proper divisors (1).

11821081 is an equidigital number, since it uses as much as digits as its factorization.

11821081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 128, while the sum is 22.

The square root of 11821081 is about 3438.1798963987. The cubic root of 11821081 is about 227.7993065689.

Adding to 11821081 its reverse (18012811), we get a palindrome (29833892).

The spelling of 11821081 in words is "eleven million, eight hundred twenty-one thousand, eighty-one".