111665543551 has 4 divisors (see below), whose sum is σ = 111675620952. Its totient is φ = 111655466152.

The previous prime is 111665543543. The next prime is 111665543567. The reversal of 111665543551 is 155345566111.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 111665543551 - 2³ = 111665543543 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 111665543498 and 111665543507.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (111665543051) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5022061 + ... + 5044246.

It is an arithmetic number, because the mean of its divisors is an integer number (27918905238).

Almost surely, 2^111665543551 is an apocalyptic number.

111665543551 is a deficient number, since it is larger than the sum of its proper divisors (10077401).

111665543551 is a wasteful number, since it uses less digits than its factorization.

111665543551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10077400.

The product of its digits is 270000, while the sum is 43.

The spelling of 111665543551 in words is "one hundred eleven billion, six hundred sixty-five million, five hundred forty-three thousand, five hundred fifty-one".