211891172 has 6 divisors (see below), whose sum is σ = 370809558. Its totient is φ = 105945584.

The previous prime is 211891153. The next prime is 211891189. The reversal of 211891172 is 271198112.

211891172 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 156150016 + 55741156 = 12496^2 + 7466^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 26486393 + ... + 26486400.

It is an arithmetic number, because the mean of its divisors is an integer number (61801593).

Almost surely, 2^211891172 is an apocalyptic number.

It is an amenable number.

211891172 is a deficient number, since it is larger than the sum of its proper divisors (158918386).

211891172 is a wasteful number, since it uses less digits than its factorization.

211891172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52972797 (or 52972795 counting only the distinct ones).

The product of its digits is 2016, while the sum is 32.

The square root of 211891172 is about 14556.4821299653. The cubic root of 211891172 is about 596.1711480916.

The spelling of 211891172 in words is "two hundred eleven million, eight hundred ninety-one thousand, one hundred seventy-two".