1213201221 has 8 divisors (see below), whose sum is σ = 1624047264. Its totient is φ = 805578000.

The previous prime is 1213201201. The next prime is 1213201237. The reversal of 1213201221 is 1221023121.

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

It is not a de Polignac number, because 1213201221 - 2²⁵ = 1179646789 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1213201221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1213201201) 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, 804826 + ... + 806331.

It is an arithmetic number, because the mean of its divisors is an integer number (203005908).

Almost surely, 2^1213201221 is an apocalyptic number.

It is an amenable number.

1213201221 is a deficient number, since it is larger than the sum of its proper divisors (410846043).

1213201221 is a wasteful number, since it uses less digits than its factorization.

1213201221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1611411.

The product of its (nonzero) digits is 48, while the sum is 15.

The square root of 1213201221 is about 34831.0381843551. The cubic root of 1213201221 is about 1066.5411415548.

Adding to 1213201221 its reverse (1221023121), we get a palindrome (2434224342).

The spelling of 1213201221 in words is "one billion, two hundred thirteen million, two hundred one thousand, two hundred twenty-one".