111720221511 has 8 divisors (see below), whose sum is σ = 148968743040. Its totient is φ = 74475923832.

The previous prime is 111720221497. The next prime is 111720221603. The reversal of 111720221511 is 115122027111.

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

It is not a de Polignac number, because 111720221511 - 2⁵ = 111720221479 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (111720221611) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 993721 + ... + 1100418.

It is an arithmetic number, because the mean of its divisors is an integer number (18621092880).

Almost surely, 2^111720221511 is an apocalyptic number.

111720221511 is a deficient number, since it is larger than the sum of its proper divisors (37248521529).

111720221511 is a wasteful number, since it uses less digits than its factorization.

111720221511 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2111925.

The product of its (nonzero) digits is 280, while the sum is 24.

Adding to 111720221511 its reverse (115122027111), we get a palindrome (226842248622).

The spelling of 111720221511 in words is "one hundred eleven billion, seven hundred twenty million, two hundred twenty-one thousand, five hundred eleven".