11211025561 has 4 divisors (see below), whose sum is σ = 11226447232. Its totient is φ = 11195603892.

The previous prime is 11211025543. The next prime is 11211025577. The reversal of 11211025561 is 16552011211.

11211025561 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 11211025561 - 2¹⁹ = 11210501273 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11211025541) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7709745 + ... + 7711198.

It is an arithmetic number, because the mean of its divisors is an integer number (2806611808).

Almost surely, 2^11211025561 is an apocalyptic number.

It is an amenable number.

11211025561 is a deficient number, since it is larger than the sum of its proper divisors (15421671).

11211025561 is an equidigital number, since it uses as much as digits as its factorization.

11211025561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15421670.

The product of its (nonzero) digits is 600, while the sum is 25.

Adding to 11211025561 its reverse (16552011211), we get a palindrome (27763036772).

The spelling of 11211025561 in words is "eleven billion, two hundred eleven million, twenty-five thousand, five hundred sixty-one".