111001200021 has 12 divisors (see below), whose sum is σ = 164668447372. Its totient is φ = 72000778176.

The previous prime is 111001199971. The next prime is 111001200029. The reversal of 111001200021 is 120002100111.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 71305020900 + 39696179121 = 267030^2 + 199239^2 .

It is not a de Polignac number, because 111001200021 - 2⁷ = 111001199893 is a prime.

It is a super-2 number, since 2×111001200021² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 111001199976 and 111001200012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (111001200029) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 166668136 + ... + 166668801.

Almost surely, 2^111001200021 is an apocalyptic number.

It is an amenable number.

111001200021 is a deficient number, since it is larger than the sum of its proper divisors (53667247351).

111001200021 is a wasteful number, since it uses less digits than its factorization.

111001200021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 333336980 (or 333336977 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

Adding to 111001200021 its reverse (120002100111), we get a palindrome (231003300132).

It can be divided in two parts, 11100 and 1200021, that added together give a palindrome (1211121).

The spelling of 111001200021 in words is "one hundred eleven billion, one million, two hundred thousand, twenty-one".