1221100221112 has 8 divisors (see below), whose sum is σ = 2289562914600. Its totient is φ = 610550110552.

The previous prime is 1221100221043. The next prime is 1221100221119. The reversal of 1221100221112 is 2111220011221.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221100221119) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 76318763812 + ... + 76318763827.

It is an arithmetic number, because the mean of its divisors is an integer number (286195364325).

Almost surely, 2^{1221100221112} is an apocalyptic number.

It is an amenable number.

1221100221112 is a deficient number, since it is larger than the sum of its proper divisors (1068462693488).

1221100221112 is a wasteful number, since it uses less digits than its factorization.

1221100221112 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 152637527645 (or 152637527641 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 1221100221112 its reverse (2111220011221), we get a palindrome (3332320232333).

The spelling of 1221100221112 in words is "one trillion, two hundred twenty-one billion, one hundred million, two hundred twenty-one thousand, one hundred twelve".