11920561 has 2 divisors, whose sum is σ = 11920562. Its totient is φ = 11920560.

The previous prime is 11920541. The next prime is 11920591. The reversal of 11920561 is 16502911.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6426225 + 5494336 = 2535^2 + 2344^2 .

It is an emirp because it is prime and its reverse (16502911) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 11920561 - 2⁵ = 11920529 is a prime.

It is not a weakly prime, because it can be changed into another prime (11920511) 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, 5960280 + 5960281.

It is an arithmetic number, because the mean of its divisors is an integer number (5960281).

Almost surely, 2^11920561 is an apocalyptic number.

It is an amenable number.

11920561 is a deficient number, since it is larger than the sum of its proper divisors (1).

11920561 is an equidigital number, since it uses as much as digits as its factorization.

11920561 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 540, while the sum is 25.

The square root of 11920561 is about 3452.6165440141. The cubic root of 11920561 is about 228.4365354186.

The spelling of 11920561 in words is "eleven million, nine hundred twenty thousand, five hundred sixty-one".