212100111 has 12 divisors (see below), whose sum is σ = 311390040. Its totient is φ = 139081680.

The previous prime is 212100079. The next prime is 212100121. The reversal of 212100111 is 111001212.

It is a happy number.

It is not a de Polignac number, because 212100111 - 2⁵ = 212100079 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 = 212100093 and 212100102.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212100121) 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, 192621 + ... + 193718.

It is an arithmetic number, because the mean of its divisors is an integer number (25949170).

Almost surely, 2^212100111 is an apocalyptic number.

212100111 is a deficient number, since it is larger than the sum of its proper divisors (99289929).

212100111 is a wasteful number, since it uses less digits than its factorization.

212100111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 386406 (or 386403 counting only the distinct ones).

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

The square root of 212100111 is about 14563.6571986572. The cubic root of 212100111 is about 596.3670387180.

Adding to 212100111 its reverse (111001212), we get a palindrome (323101323).

The spelling of 212100111 in words is "two hundred twelve million, one hundred thousand, one hundred eleven".