11505120121055 has 16 divisors (see below), whose sum is σ = 15064600640544. Its totient is φ = 8365497598080.

The previous prime is 11505120121051. The next prime is 11505120121097. The reversal of 11505120121055 is 55012102150511.

It is not a de Polignac number, because 11505120121055 - 2² = 11505120121051 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11505120121051) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 23031764 + ... + 23525993.

It is an arithmetic number, because the mean of its divisors is an integer number (941537540034).

Almost surely, 2^{11505120121055} is an apocalyptic number.

11505120121055 is a deficient number, since it is larger than the sum of its proper divisors (3559480519489).

11505120121055 is a wasteful number, since it uses less digits than its factorization.

11505120121055 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46562266.

The product of its (nonzero) digits is 2500, while the sum is 29.

Adding to 11505120121055 its reverse (55012102150511), we get a palindrome (66517222271566).

The spelling of 11505120121055 in words is "eleven trillion, five hundred five billion, one hundred twenty million, one hundred twenty-one thousand, fifty-five".