111221131655 has 8 divisors (see below), whose sum is σ = 133467288192. Its totient is φ = 88975618528.

The previous prime is 111221131631. The next prime is 111221131663. The reversal of 111221131655 is 556131122111.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 111221131655 - 2³⁶ = 42501654919 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 392522 + ... + 613608.

It is an arithmetic number, because the mean of its divisors is an integer number (16683411024).

Almost surely, 2^111221131655 is an apocalyptic number.

111221131655 is a deficient number, since it is larger than the sum of its proper divisors (22246156537).

111221131655 is a wasteful number, since it uses less digits than its factorization.

111221131655 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 321705.

The product of its digits is 1800, while the sum is 29.

Adding to 111221131655 its reverse (556131122111), we get a palindrome (667352253766).

The spelling of 111221131655 in words is "one hundred eleven billion, two hundred twenty-one million, one hundred thirty-one thousand, six hundred fifty-five".