1221021222211 has 8 divisors (see below), whose sum is σ = 1427905217024. Its totient is φ = 1022250325320.

The previous prime is 1221021222203. The next prime is 1221021222217. The reversal of 1221021222211 is 1122221201221.

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

It is not a de Polignac number, because 1221021222211 - 2³ = 1221021222203 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221021222217) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2028274155 + ... + 2028274756.

It is an arithmetic number, because the mean of its divisors is an integer number (178488152128).

Almost surely, 2^{1221021222211} is an apocalyptic number.

1221021222211 is a deficient number, since it is larger than the sum of its proper divisors (206883994813).

1221021222211 is an equidigital number, since it uses as much as digits as its factorization.

1221021222211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4056548961.

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

Adding to 1221021222211 its reverse (1122221201221), we get a palindrome (2343242423432).

The spelling of 1221021222211 in words is "one trillion, two hundred twenty-one billion, twenty-one million, two hundred twenty-two thousand, two hundred eleven".