11555616660121 has 4 divisors (see below), whose sum is σ = 11633171134500. Its totient is φ = 11478062185744.

The previous prime is 11555616660073. The next prime is 11555616660131. The reversal of 11555616660121 is 12106661655511.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 422416804096 + 11133199856025 = 649936^2 + 3336645^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11555616660121 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11555616660131) 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, 38777236966 + ... + 38777237263.

It is an arithmetic number, because the mean of its divisors is an integer number (2908292783625).

Almost surely, 2^{11555616660121} is an apocalyptic number.

It is an amenable number.

11555616660121 is a deficient number, since it is larger than the sum of its proper divisors (77554474379).

11555616660121 is an equidigital number, since it uses as much as digits as its factorization.

11555616660121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77554474378.

The product of its (nonzero) digits is 324000, while the sum is 46.

The spelling of 11555616660121 in words is "eleven trillion, five hundred fifty-five billion, six hundred sixteen million, six hundred sixty thousand, one hundred twenty-one".