212021100172 has 72 divisors (see below), whose sum is σ = 435854034000. Its totient is φ = 89974717056.

The previous prime is 212021100143. The next prime is 212021100173. The reversal of 212021100172 is 271001120212.

212021100172 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is not an unprimeable number, because it can be changed into a prime (212021100173) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 57659598 + ... + 57663274.

It is an arithmetic number, because the mean of its divisors is an integer number (6053528250).

Almost surely, 2^212021100172 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 212021100172, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (217927017000).

212021100172 is an abundant number, since it is smaller than the sum of its proper divisors (223832933828).

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

212021100172 is a wasteful number, since it uses less digits than its factorization.

212021100172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6503 (or 6494 counting only the distinct ones).

The product of its (nonzero) digits is 112, while the sum is 19.

Adding to 212021100172 its reverse (271001120212), we get a palindrome (483022220384).

The spelling of 212021100172 in words is "two hundred twelve billion, twenty-one million, one hundred thousand, one hundred seventy-two".