111211010111021 has 4 divisors (see below), whose sum is σ = 111624433940700. Its totient is φ = 110797586281344.

The previous prime is 111211010110999. The next prime is 111211010111041. The reversal of 111211010111021 is 120111010112111.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 38835393558025 + 72375616552996 = 6231805^2 + 8507386^2 .

It is a cyclic number.

It is not a de Polignac number, because 111211010111021 - 2⁶ = 111211010110957 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 111211010110987 and 111211010111005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (111211010111041) 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, 206711914436 + ... + 206711914973.

It is an arithmetic number, because the mean of its divisors is an integer number (27906108485175).

Almost surely, 2^{111211010111021} is an apocalyptic number.

It is an amenable number.

111211010111021 is a deficient number, since it is larger than the sum of its proper divisors (413423829679).

111211010111021 is an equidigital number, since it uses as much as digits as its factorization.

111211010111021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 413423829678.

The product of its (nonzero) digits is 4, while the sum is 14.

Adding to 111211010111021 its reverse (120111010112111), we get a palindrome (231322020223132).

The spelling of 111211010111021 in words is "one hundred eleven trillion, two hundred eleven billion, ten million, one hundred eleven thousand, twenty-one".