210000021111 has 12 divisors (see below), whose sum is σ = 306741605040. Its totient is φ = 138426979680.

The previous prime is 210000021107. The next prime is 210000021149. The reversal of 210000021111 is 111120000012.

It is a happy number.

It is not a de Polignac number, because 210000021111 - 2² = 210000021107 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 210000021093 and 210000021102.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (210000021151) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 131085355 + ... + 131086956.

It is an arithmetic number, because the mean of its divisors is an integer number (25561800420).

Almost surely, 2^210000021111 is an apocalyptic number.

210000021111 is a deficient number, since it is larger than the sum of its proper divisors (96741583929).

210000021111 is a wasteful number, since it uses less digits than its factorization.

210000021111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 262172406 (or 262172403 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

Adding to 210000021111 its reverse (111120000012), we get a palindrome (321120021123).

The spelling of 210000021111 in words is "two hundred ten billion, twenty-one thousand, one hundred eleven".