11865521 has 2 divisors, whose sum is σ = 11865522. Its totient is φ = 11865520.

The previous prime is 11865509. The next prime is 11865533. The reversal of 11865521 is 12556811.

11865521 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a balanced prime because it is at equal distance from previous prime (11865509) and next prime (11865533).

It can be written as a sum of positive squares in only one way, i.e., 10080625 + 1784896 = 3175^2 + 1336^2 .

It is an emirp because it is prime and its reverse (12556811) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 11865521 - 2¹⁰ = 11864497 is a prime.

It is not a weakly prime, because it can be changed into another prime (11865571) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5932760 + 5932761.

It is an arithmetic number, because the mean of its divisors is an integer number (5932761).

Almost surely, 2^11865521 is an apocalyptic number.

It is an amenable number.

11865521 is a deficient number, since it is larger than the sum of its proper divisors (1).

11865521 is an equidigital number, since it uses as much as digits as its factorization.

11865521 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2400, while the sum is 29.

The square root of 11865521 is about 3444.6365555745. The cubic root of 11865521 is about 228.0844113939.

The spelling of 11865521 in words is "eleven million, eight hundred sixty-five thousand, five hundred twenty-one".