212111100 has 54 divisors (see below), whose sum is σ = 664853280. Its totient is φ = 56562720.

The previous prime is 212111099. The next prime is 212111101. The reversal of 212111100 is 1111212.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (212111099) and next prime (212111101).

It is a super-2 number, since 2×212111100² = 89982237486420000, which contains 22 as substring.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212111101) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 116940 + ... + 118739.

Almost surely, 2^212111100 is an apocalyptic number.

212111100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

212111100 is an abundant number, since it is smaller than the sum of its proper divisors (452742180).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

212111100 is a wasteful number, since it uses less digits than its factorization.

212111100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 235699 (or 235689 counting only the distinct ones).

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

The square root of 212111100 is about 14564.0344685118. The cubic root of 212111100 is about 596.3773378863.

Adding to 212111100 its reverse (1111212), we get a palindrome (213222312).

The spelling of 212111100 in words is "two hundred twelve million, one hundred eleven thousand, one hundred".