210111210021 has 8 divisors (see below), whose sum is σ = 282163735840. Its totient is φ = 139066412112.

The previous prime is 210111210013. The next prime is 210111210103. The reversal of 210111210021 is 120012111012.

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

It is not a de Polignac number, because 210111210021 - 2³ = 210111210013 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 = 210111209979 and 210111210006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (210111210521) 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, 251931490 + ... + 251932323.

It is an arithmetic number, because the mean of its divisors is an integer number (35270466980).

Almost surely, 2^210111210021 is an apocalyptic number.

It is an amenable number.

210111210021 is a deficient number, since it is larger than the sum of its proper divisors (72052525819).

210111210021 is a wasteful number, since it uses less digits than its factorization.

210111210021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 503863955.

The product of its (nonzero) digits is 8, while the sum is 12.

Adding to 210111210021 its reverse (120012111012), we get a palindrome (330123321033).

Subtracting from 210111210021 its reverse (120012111012), we obtain a palindrome (90099099009).

The spelling of 210111210021 in words is "two hundred ten billion, one hundred eleven million, two hundred ten thousand, twenty-one".