211021021172 has 12 divisors (see below), whose sum is σ = 397693463076. Its totient is φ = 97394317440.

The previous prime is 211021021171. The next prime is 211021021213. The reversal of 211021021172 is 271120120112.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 21808200976 + 189212820196 = 147676^2 + 434986^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211021021171) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2029048229 + ... + 2029048332.

It is an arithmetic number, because the mean of its divisors is an integer number (33141121923).

Almost surely, 2^211021021172 is an apocalyptic number.

It is an amenable number.

211021021172 is a deficient number, since it is larger than the sum of its proper divisors (186672441904).

211021021172 is a wasteful number, since it uses less digits than its factorization.

211021021172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4058096578 (or 4058096576 counting only the distinct ones).

The product of its (nonzero) digits is 112, while the sum is 20.

Adding to 211021021172 its reverse (271120120112), we get a palindrome (482141141284).

The spelling of 211021021172 in words is "two hundred eleven billion, twenty-one million, twenty-one thousand, one hundred seventy-two".