111000100021 has 4 divisors (see below), whose sum is σ = 111109676652. Its totient is φ = 110890523392.

The previous prime is 111000100019. The next prime is 111000100027. The reversal of 111000100021 is 120001000111.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 120001000111 = 877 ⋅136831243.

It can be written as a sum of positive squares in 2 ways, for example, as 13210054225 + 97790045796 = 114935^2 + 312714^2 .

It is a cyclic number.

It is not a de Polignac number, because 111000100021 - 2¹ = 111000100019 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 111000099977 and 111000100013.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (111000100027) 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, 54786796 + ... + 54788821.

It is an arithmetic number, because the mean of its divisors is an integer number (27777419163).

Almost surely, 2^111000100021 is an apocalyptic number.

It is an amenable number.

111000100021 is a deficient number, since it is larger than the sum of its proper divisors (109576631).

111000100021 is a wasteful number, since it uses less digits than its factorization.

111000100021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109576630.

The product of its (nonzero) digits is 2, while the sum is 7.

Adding to 111000100021 its reverse (120001000111), we get a palindrome (231001100132).

The spelling of 111000100021 in words is "one hundred eleven billion, one hundred thousand, twenty-one".