11910850561 has 2 divisors, whose sum is σ = 11910850562. Its totient is φ = 11910850560.

The previous prime is 11910850559. The next prime is 11910850577. The reversal of 11910850561 is 16505801911.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11612217600 + 298632961 = 107760^2 + 17281^2 .

It is an emirp because it is prime and its reverse (16505801911) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 11910850561 - 2¹ = 11910850559 is a prime.

It is a super-2 number, since 2×11910850561² (a number of 21 digits) contains 22 as substring.

Together with 11910850559, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 11910850561.

It is not a weakly prime, because it can be changed into another prime (11910650561) 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, 5955425280 + 5955425281.

It is an arithmetic number, because the mean of its divisors is an integer number (5955425281).

Almost surely, 2^11910850561 is an apocalyptic number.

It is an amenable number.

11910850561 is a deficient number, since it is larger than the sum of its proper divisors (1).

11910850561 is an equidigital number, since it uses as much as digits as its factorization.

11910850561 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10800, while the sum is 37.

The spelling of 11910850561 in words is "eleven billion, nine hundred ten million, eight hundred fifty thousand, five hundred sixty-one".