211111111021021 has 8 divisors (see below), whose sum is σ = 211163589386784. Its totient is φ = 211058639190000.

The previous prime is 211111111021009. The next prime is 211111111021073. The reversal of 211111111021021 is 120120111111112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 211111111021021 - 2¹⁹ = 211111110496733 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 211111111020986 and 211111111021004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211111111021001) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 63306646 + ... + 66557896.

It is an arithmetic number, because the mean of its divisors is an integer number (26395448673348).

Almost surely, 2^{211111111021021} is an apocalyptic number.

It is an amenable number.

211111111021021 is a deficient number, since it is larger than the sum of its proper divisors (52478365763).

211111111021021 is an equidigital number, since it uses as much as digits as its factorization.

211111111021021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3267371.

The product of its (nonzero) digits is 8, while the sum is 16.

Adding to 211111111021021 its reverse (120120111111112), we get a palindrome (331231222132133).

Subtracting from 211111111021021 its reverse (120120111111112), we obtain a palindrome (90990999909909).

The spelling of 211111111021021 in words is "two hundred eleven trillion, one hundred eleven billion, one hundred eleven million, twenty-one thousand, twenty-one".