111561110001 has 16 divisors (see below), whose sum is σ = 180300784320. Its totient is φ = 67612793760.

The previous prime is 111561109991. The next prime is 111561110051. The reversal of 111561110001 is 100011165111.

It is a happy number.

111561110001 is a `hidden beast` number, since 1 + 1 + 1 + 561 + 1 + 100 + 0 + 1 = 666.

It is not a de Polignac number, because 111561110001 - 2⁶ = 111561109937 is a prime.

It is not an unprimeable number, because it can be changed into a prime (111561110051) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 187813020 + ... + 187813613.

It is an arithmetic number, because the mean of its divisors is an integer number (11268799020).

Almost surely, 2^111561110001 is an apocalyptic number.

111561110001 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

111561110001 is a deficient number, since it is larger than the sum of its proper divisors (68739674319).

111561110001 is a wasteful number, since it uses less digits than its factorization.

111561110001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 375626653 (or 375626647 counting only the distinct ones).

The product of its (nonzero) digits is 30, while the sum is 18.

Adding to 111561110001 its reverse (100011165111), we get a palindrome (211572275112).

It can be divided in two parts, 1115 and 61110001, that added together give a palindrome (61111116).

The spelling of 111561110001 in words is "one hundred eleven billion, five hundred sixty-one million, one hundred ten thousand, one".