1221012101111 has 16 divisors (see below), whose sum is σ = 1390523258880. Its totient is φ = 1061294039520.

The previous prime is 1221012101039. The next prime is 1221012101117. The reversal of 1221012101111 is 1111012101221.

It is a de Polignac number, because none of the positive numbers 2^k-1221012101111 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 (1221012101117) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 444071 + ... + 1624568.

It is an arithmetic number, because the mean of its divisors is an integer number (86907703680).

Almost surely, 2^{1221012101111} is an apocalyptic number.

1221012101111 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1221012101111 is a deficient number, since it is larger than the sum of its proper divisors (169511157769).

1221012101111 is a wasteful number, since it uses less digits than its factorization.

1221012101111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2071006.

The product of its (nonzero) digits is 8, while the sum is 14.

Adding to 1221012101111 its reverse (1111012101221), we get a palindrome (2332024202332).

The spelling of 1221012101111 in words is "one trillion, two hundred twenty-one billion, twelve million, one hundred one thousand, one hundred eleven".