111135721 has 4 divisors (see below), whose sum is σ = 111212244. Its totient is φ = 111059200.

The previous prime is 111135709. The next prime is 111135797. The reversal of 111135721 is 127531111.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 127531111 = 4241 ⋅30071.

It can be written as a sum of positive squares in 2 ways, for example, as 78234025 + 32901696 = 8845^2 + 5736^2 .

It is a cyclic number.

It is not a de Polignac number, because 111135721 - 2⁷ = 111135593 is a prime.

It is a super-2 number, since 2×111135721² = 24702296964379682, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 111135692 and 111135701.

It is not an unprimeable number, because it can be changed into a prime (111135421) 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, 36040 + ... + 39001.

It is an arithmetic number, because the mean of its divisors is an integer number (27803061).

Almost surely, 2^111135721 is an apocalyptic number.

It is an amenable number.

111135721 is a deficient number, since it is larger than the sum of its proper divisors (76523).

111135721 is an equidigital number, since it uses as much as digits as its factorization.

111135721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 76522.

The product of its digits is 210, while the sum is 22.

The square root of 111135721 is about 10542.0928187908. The cubic root of 111135721 is about 480.7853477507.

Adding to 111135721 its reverse (127531111), we get a palindrome (238666832).

The spelling of 111135721 in words is "one hundred eleven million, one hundred thirty-five thousand, seven hundred twenty-one".