11981603 has 2 divisors, whose sum is σ = 11981604. Its totient is φ = 11981602.

The previous prime is 11981587. The next prime is 11981623. The reversal of 11981603 is 30618911.

It is a happy number.

11981603 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 11981603 - 2⁴ = 11981587 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (11981623) 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, 5990801 + 5990802.

It is an arithmetic number, because the mean of its divisors is an integer number (5990802).

Almost surely, 2^11981603 is an apocalyptic number.

11981603 is a deficient number, since it is larger than the sum of its proper divisors (1).

11981603 is an equidigital number, since it uses as much as digits as its factorization.

11981603 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1296, while the sum is 29.

The square root of 11981603 is about 3461.4452184023. The cubic root of 11981603 is about 228.8257925163.

The spelling of 11981603 in words is "eleven million, nine hundred eighty-one thousand, six hundred three".