11611643921569 has 2 divisors, whose sum is σ = 11611643921570. Its totient is φ = 11611643921568.

The previous prime is 11611643921567. The next prime is 11611643921587. The reversal of 11611643921569 is 96512934611611.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 9981650390625 + 1629993530944 = 3159375^2 + 1276712^2 .

It is a cyclic number.

It is not a de Polignac number, because 11611643921569 - 2¹ = 11611643921567 is a prime.

It is a super-2 number, since 2×11611643921569² (a number of 27 digits) contains 22 as substring.

Together with 11611643921567, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (11611643921561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5805821960784 + 5805821960785.

It is an arithmetic number, because the mean of its divisors is an integer number (5805821960785).

Almost surely, 2^{11611643921569} is an apocalyptic number.

It is an amenable number.

11611643921569 is a deficient number, since it is larger than the sum of its proper divisors (1).

11611643921569 is an equidigital number, since it uses as much as digits as its factorization.

11611643921569 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2099520, while the sum is 55.

The spelling of 11611643921569 in words is "eleven trillion, six hundred eleven billion, six hundred forty-three million, nine hundred twenty-one thousand, five hundred sixty-nine".