1211222211 has 16 divisors (see below), whose sum is σ = 1622897664. Its totient is φ = 803525184.

The previous prime is 1211222191. The next prime is 1211222213. The reversal of 1211222211 is 1122221121.

It is not a de Polignac number, because 1211222211 - 2¹¹ = 1211220163 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1211222213) 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, 678426 + ... + 680208.

It is an arithmetic number, because the mean of its divisors is an integer number (101431104).

Almost surely, 2^1211222211 is an apocalyptic number.

1211222211 is a deficient number, since it is larger than the sum of its proper divisors (411675453).

1211222211 is a wasteful number, since it uses less digits than its factorization.

1211222211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2770.

The product of its digits is 32, while the sum is 15.

The square root of 1211222211 is about 34802.6178756714. The cubic root of 1211222211 is about 1065.9609013699.

Adding to 1211222211 its reverse (1122221121), we get a palindrome (2333443332).

The spelling of 1211222211 in words is "one billion, two hundred eleven million, two hundred twenty-two thousand, two hundred eleven".