11155861 has 2 divisors, whose sum is σ = 11155862. Its totient is φ = 11155860.

The previous prime is 11155849. The next prime is 11155867. The reversal of 11155861 is 16855111.

11155861 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 8814961 + 2340900 = 2969^2 + 1530^2 .

It is a cyclic number.

It is not a de Polignac number, because 11155861 - 2¹⁹ = 10631573 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11155867) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5577930 + 5577931.

It is an arithmetic number, because the mean of its divisors is an integer number (5577931).

Almost surely, 2^11155861 is an apocalyptic number.

It is an amenable number.

11155861 is a deficient number, since it is larger than the sum of its proper divisors (1).

11155861 is an equidigital number, since it uses as much as digits as its factorization.

11155861 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1200, while the sum is 28.

The square root of 11155861 is about 3340.0390716278. The cubic root of 11155861 is about 223.4434859205.

The spelling of 11155861 in words is "eleven million, one hundred fifty-five thousand, eight hundred sixty-one".