111661556555 has 16 divisors (see below), whose sum is σ = 143071315200. Its totient is φ = 83458259808.

The previous prime is 111661556519. The next prime is 111661556561. The reversal of 111661556555 is 555655166111.

It is a cyclic number.

It is not a de Polignac number, because 111661556555 - 2³⁰ = 110587814731 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11285405 + ... + 11295294.

It is an arithmetic number, because the mean of its divisors is an integer number (8941957200).

Almost surely, 2^111661556555 is an apocalyptic number.

111661556555 is a deficient number, since it is larger than the sum of its proper divisors (31409758645).

111661556555 is a wasteful number, since it uses less digits than its factorization.

111661556555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22580770.

The product of its digits is 675000, while the sum is 47.

The spelling of 111661556555 in words is "one hundred eleven billion, six hundred sixty-one million, five hundred fifty-six thousand, five hundred fifty-five".