211889221 has 4 divisors (see below), whose sum is σ = 212128992. Its totient is φ = 211649452.

The previous prime is 211889203. The next prime is 211889233. The reversal of 211889221 is 122988112.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 211889221 - 2²¹ = 209792069 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211889201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 118555 + ... + 120328.

It is an arithmetic number, because the mean of its divisors is an integer number (53032248).

Almost surely, 2^211889221 is an apocalyptic number.

It is an amenable number.

211889221 is a deficient number, since it is larger than the sum of its proper divisors (239771).

211889221 is an equidigital number, since it uses as much as digits as its factorization.

211889221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 239770.

The product of its digits is 4608, while the sum is 34.

The square root of 211889221 is about 14556.4151149931. The cubic root of 211889221 is about 596.1693183260.

The spelling of 211889221 in words is "two hundred eleven million, eight hundred eighty-nine thousand, two hundred twenty-one".