210111211111021 has 16 divisors (see below), whose sum is σ = 229727830183488. Its totient is φ = 190580973184000.

The previous prime is 210111211110961. The next prime is 210111211111049. The reversal of 210111211111021 is 120111112111012.

It is a cyclic number.

It is not a de Polignac number, because 210111211111021 - 2¹⁵ = 210111211078253 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 210111211110986 and 210111211111004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (210111211112021) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1810555 + ... + 20579128.

It is an arithmetic number, because the mean of its divisors is an integer number (14357989386468).

Almost surely, 2^{210111211111021} is an apocalyptic number.

It is an amenable number.

210111211111021 is a deficient number, since it is larger than the sum of its proper divisors (19616619072467).

210111211111021 is a wasteful number, since it uses less digits than its factorization.

210111211111021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22391612.

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

Adding to 210111211111021 its reverse (120111112111012), we get a palindrome (330222323222033).

Subtracting from 210111211111021 its reverse (120111112111012), we obtain a palindrome (90000099000009).

The spelling of 210111211111021 in words is "two hundred ten trillion, one hundred eleven billion, two hundred eleven million, one hundred eleven thousand, twenty-one".