212122121100 has 144 divisors (see below), whose sum is σ = 652063994400. Its totient is φ = 53139179520.

The previous prime is 212122121051. The next prime is 212122121143. The reversal of 212122121100 is 1121221212.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 212122121100.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 7585 + ... + 651384.

Almost surely, 2^212122121100 is an apocalyptic number.

212122121100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 212122121100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (326031997200).

212122121100 is an abundant number, since it is smaller than the sum of its proper divisors (439941873300).

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

212122121100 is a wasteful number, since it uses less digits than its factorization.

212122121100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 659052 (or 659045 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 212122121100 its reverse (1121221212), we get a palindrome (213243342312).

The spelling of 212122121100 in words is "two hundred twelve billion, one hundred twenty-two million, one hundred twenty-one thousand, one hundred".