1221202211 has 4 divisors (see below), whose sum is σ = 1233293424. Its totient is φ = 1209111000.

The previous prime is 1221202183. The next prime is 1221202223. The reversal of 1221202211 is 1122021221.

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

It is a cyclic number.

It is not a de Polignac number, because 1221202211 - 2¹⁴ = 1221185827 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221202291) 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, 6045455 + ... + 6045656.

It is an arithmetic number, because the mean of its divisors is an integer number (308323356).

Almost surely, 2^1221202211 is an apocalyptic number.

1221202211 is a deficient number, since it is larger than the sum of its proper divisors (12091213).

1221202211 is a wasteful number, since it uses less digits than its factorization.

1221202211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12091212.

The product of its (nonzero) digits is 32, while the sum is 14.

The square root of 1221202211 is about 34945.7037559698. The cubic root of 1221202211 is about 1068.8805980370.

Adding to 1221202211 its reverse (1122021221), we get a palindrome (2343223432).

The spelling of 1221202211 in words is "one billion, two hundred twenty-one million, two hundred two thousand, two hundred eleven".