211201209 has 16 divisors (see below), whose sum is σ = 320523840. Its totient is φ = 137365920.

The previous prime is 211201147. The next prime is 211201223. The reversal of 211201209 is 902102112.

It is not a de Polignac number, because 211201209 - 2¹¹ = 211199161 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 211201191 and 211201200.

It is not an unprimeable number, because it can be changed into a prime (211201909) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 94287 + ... + 96500.

It is an arithmetic number, because the mean of its divisors is an integer number (20032740).

Almost surely, 2^211201209 is an apocalyptic number.

It is an amenable number.

211201209 is a deficient number, since it is larger than the sum of its proper divisors (109322631).

211201209 is a wasteful number, since it uses less digits than its factorization.

211201209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 190837 (or 190831 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 18.

The square root of 211201209 is about 14532.7632953957. The cubic root of 211201209 is about 595.5233575215.

The spelling of 211201209 in words is "two hundred eleven million, two hundred one thousand, two hundred nine".