11505121155 has 48 divisors (see below), whose sum is σ = 22030594560. Its totient is φ = 5507611200.

The previous prime is 11505121153. The next prime is 11505121163. The reversal of 11505121155 is 55112150511.

It is a happy number.

11505121155 is a `hidden beast` number, since 1 + 1 + 505 + 1 + 2 + 1 + 155 = 666.

11505121155 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 11505121155 - 2¹ = 11505121153 is a prime.

It is not an unprimeable number, because it can be changed into a prime (11505121153) 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 47 ways as a sum of consecutive naturals, for example, 108001 + ... + 186210.

It is an arithmetic number, because the mean of its divisors is an integer number (458970720).

Almost surely, 2^11505121155 is an apocalyptic number.

11505121155 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

11505121155 is a deficient number, since it is larger than the sum of its proper divisors (10525473405).

11505121155 is a wasteful number, since it uses less digits than its factorization.

11505121155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 294312 (or 294309 counting only the distinct ones).

The product of its (nonzero) digits is 1250, while the sum is 27.

Adding to 11505121155 its reverse (55112150511), we get a palindrome (66617271666).

The spelling of 11505121155 in words is "eleven billion, five hundred five million, one hundred twenty-one thousand, one hundred fifty-five".