111111555556 has 9 divisors (see below), whose sum is σ = 194446388899. Its totient is φ = 55555444444.

The previous prime is 111111555487. The next prime is 111111555587. The reversal of 111111555556 is 655555111111.

It is a happy number.

The square root of 111111555556 is 333334.

It is a perfect power (a square), and thus also a powerful number.

It is a Duffinian number.

It is a plaindrome in base 10.

It is an unprimeable number.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 583335 + ... + 750001.

Almost surely, 2^111111555556 is an apocalyptic number.

111111555556 is the 333334-th square number.

It is an amenable number.

111111555556 is a deficient number, since it is larger than the sum of its proper divisors (83334833343).

111111555556 is an frugal number, since it uses more digits than its factorization.

111111555556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 333338 (or 166669 counting only the distinct ones).

The product of its digits is 18750, while the sum is 37.

Adding to 111111555556 its reverse (655555111111), we get a palindrome (766666666667).

It can be divided in two parts, 111111 and 555556, that multiplied together give a palindrome (61728382716).

The spelling of 111111555556 in words is "one hundred eleven billion, one hundred eleven million, five hundred fifty-five thousand, five hundred fifty-six".