11661110505 has 48 divisors (see below), whose sum is σ = 22761423360. Its totient is φ = 5471481600.

The previous prime is 11661110479. The next prime is 11661110603. The reversal of 11661110505 is 50501116611.

It is not a de Polignac number, because 11661110505 - 2⁸ = 11661110249 is a prime.

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 364620 + ... + 395309.

It is an arithmetic number, because the mean of its divisors is an integer number (474196320).

Almost surely, 2^11661110505 is an apocalyptic number.

11661110505 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

11661110505 is a deficient number, since it is larger than the sum of its proper divisors (11100312855).

11661110505 is a wasteful number, since it uses less digits than its factorization.

11661110505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 759982 (or 759979 counting only the distinct ones).

The product of its (nonzero) digits is 900, while the sum is 27.

The spelling of 11661110505 in words is "eleven billion, six hundred sixty-one million, one hundred ten thousand, five hundred five".