211016221 has 4 divisors (see below), whose sum is σ = 227248252. Its totient is φ = 194784192.

The previous prime is 211016173. The next prime is 211016233. The reversal of 211016221 is 122610112.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 60684100 + 150332121 = 7790^2 + 12261^2 .

It is a cyclic number.

It is not a de Polignac number, because 211016221 - 2¹⁵ = 210983453 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 211016195 and 211016204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211046221) 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, 8115996 + ... + 8116021.

It is an arithmetic number, because the mean of its divisors is an integer number (56812063).

Almost surely, 2^211016221 is an apocalyptic number.

It is an amenable number.

211016221 is a deficient number, since it is larger than the sum of its proper divisors (16232031).

211016221 is a wasteful number, since it uses less digits than its factorization.

211016221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16232030.

The product of its (nonzero) digits is 48, while the sum is 16.

The square root of 211016221 is about 14526.3973854497. The cubic root of 211016221 is about 595.3494367141.

Adding to 211016221 its reverse (122610112), we get a palindrome (333626333).

The spelling of 211016221 in words is "two hundred eleven million, sixteen thousand, two hundred twenty-one".