1221211 has 4 divisors (see below), whose sum is σ = 1223424. Its totient is φ = 1219000.

The previous prime is 1221197. The next prime is 1221221. The reversal of 1221211 is 1121221.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 1221211 - 2⁷ = 1221083 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221221) 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, 486 + ... + 1636.

It is an arithmetic number, because the mean of its divisors is an integer number (305856).

2^1221211 is an apocalyptic number.

1221211 is a deficient number, since it is larger than the sum of its proper divisors (2213).

1221211 is a wasteful number, since it uses less digits than its factorization.

1221211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2212.

The product of its digits is 8, while the sum is 10.

The square root of 1221211 is about 1105.0841596910. The cubic root of 1221211 is about 106.8883162278. Note that the first 3 decimals are identical.

Adding to 1221211 its sum of digits (10), we get a palindrome (1221221).

Adding to 1221211 its reverse (1121221), we get a palindrome (2342432).

The spelling of 1221211 in words is "one million, two hundred twenty-one thousand, two hundred eleven".