1221100221043 has 2 divisors, whose sum is σ = 1221100221044. Its totient is φ = 1221100221042.

The previous prime is 1221100221007. The next prime is 1221100221119. The reversal of 1221100221043 is 3401220011221.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1221100221043 - 2³³ = 1212510286451 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1221100221043.

It is not a weakly prime, because it can be changed into another prime (1221100221743) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610550110521 + 610550110522.

It is an arithmetic number, because the mean of its divisors is an integer number (610550110522).

Almost surely, 2^{1221100221043} is an apocalyptic number.

1221100221043 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221100221043 is an equidigital number, since it uses as much as digits as its factorization.

1221100221043 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 192, while the sum is 19.

Adding to 1221100221043 its reverse (3401220011221), we get a palindrome (4622320232264).

The spelling of 1221100221043 in words is "one trillion, two hundred twenty-one billion, one hundred million, two hundred twenty-one thousand, forty-three".