1221303211 has 8 divisors (see below), whose sum is σ = 1234215504. Its totient is φ = 1208407200.

The previous prime is 1221303191. The next prime is 1221303227. The reversal of 1221303211 is 1123031221.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1221303211 - 2⁵ = 1221303179 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221303271) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 199285 + ... + 205321.

It is an arithmetic number, because the mean of its divisors is an integer number (154276938).

Almost surely, 2^1221303211 is an apocalyptic number.

1221303211 is a deficient number, since it is larger than the sum of its proper divisors (12912293).

1221303211 is a wasteful number, since it uses less digits than its factorization.

1221303211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8141.

The product of its (nonzero) digits is 72, while the sum is 16.

The square root of 1221303211 is about 34947.1488250472. The cubic root of 1221303211 is about 1068.9100646187.

Adding to 1221303211 its reverse (1123031221), we get a palindrome (2344334432).

The spelling of 1221303211 in words is "one billion, two hundred twenty-one million, three hundred three thousand, two hundred eleven".