111000212120021 has 6 divisors (see below), whose sum is σ = 129122695731510. Its totient is φ = 95143038959976.

The previous prime is 111000212119987. The next prime is 111000212120033. The reversal of 111000212120021 is 120021212000111.

It can be written as a sum of positive squares in only one way, i.e., 77066802712900 + 33933409407121 = 8778770^2 + 5825239^2 .

It is not a de Polignac number, because 111000212120021 - 2⁶ = 111000212119957 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 111000212119978 and 111000212120005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (111000212120041) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1132655225666 + ... + 1132655225763.

It is an arithmetic number, because the mean of its divisors is an integer number (21520449288585).

Almost surely, 2^{111000212120021} is an apocalyptic number.

It is an amenable number.

111000212120021 is a deficient number, since it is larger than the sum of its proper divisors (18122483611489).

111000212120021 is an equidigital number, since it uses as much as digits as its factorization.

111000212120021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2265310451443 (or 2265310451436 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 111000212120021 its reverse (120021212000111), we get a palindrome (231021424120132).

The spelling of 111000212120021 in words is "one hundred eleven trillion, two hundred twelve million, one hundred twenty thousand, twenty-one".