1221222012111 has 32 divisors (see below), whose sum is σ = 1816633356480. Its totient is φ = 810812325888.

The previous prime is 1221222012097. The next prime is 1221222012181. The reversal of 1221222012111 is 1112102221221.

It is not a de Polignac number, because 1221222012111 - 2¹⁷ = 1221221881039 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221222012181) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 39793705 + ... + 39824381.

It is an arithmetic number, because the mean of its divisors is an integer number (56769792390).

Almost surely, 2^{1221222012111} is an apocalyptic number.

1221222012111 is a deficient number, since it is larger than the sum of its proper divisors (595411344369).

1221222012111 is a wasteful number, since it uses less digits than its factorization.

1221222012111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36680 (or 36674 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 1221222012111 its reverse (1112102221221), we get a palindrome (2333324233332).

The spelling of 1221222012111 in words is "one trillion, two hundred twenty-one billion, two hundred twenty-two million, twelve thousand, one hundred eleven".