1211212202221 has 8 divisors (see below), whose sum is σ = 1404902853440. Its totient is φ = 1022686635168.

The previous prime is 1211212202197. The next prime is 1211212202237. The reversal of 1211212202221 is 1222022121121.

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 1211212202221 - 2¹³ = 1211212194029 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1211212202281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1291270536 + ... + 1291271473.

It is an arithmetic number, because the mean of its divisors is an integer number (175612856680).

Almost surely, 2^{1211212202221} is an apocalyptic number.

It is an amenable number.

1211212202221 is a deficient number, since it is larger than the sum of its proper divisors (193690651219).

1211212202221 is an equidigital number, since it uses as much as digits as its factorization.

1211212202221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2582542083.

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 1211212202221 its reverse (1222022121121), we get a palindrome (2433234323342).

The spelling of 1211212202221 in words is "one trillion, two hundred eleven billion, two hundred twelve million, two hundred two thousand, two hundred twenty-one".