1221001112101 has 2 divisors, whose sum is σ = 1221001112102. Its totient is φ = 1221001112100.

The previous prime is 1221001112083. The next prime is 1221001112117. The reversal of 1221001112101 is 1012111001221.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 950236989601 + 270764122500 = 974801^2 + 520350^2 .

It is an emirp because it is prime and its reverse (1012111001221) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1221001112101 - 2¹⁷ = 1221000981029 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1221001152101) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610500556050 + 610500556051.

It is an arithmetic number, because the mean of its divisors is an integer number (610500556051).

Almost surely, 2^{1221001112101} is an apocalyptic number.

It is an amenable number.

1221001112101 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221001112101 is an equidigital number, since it uses as much as digits as its factorization.

1221001112101 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8, while the sum is 13.

Adding to 1221001112101 its reverse (1012111001221), we get a palindrome (2233112113322).

The spelling of 1221001112101 in words is "one trillion, two hundred twenty-one billion, one million, one hundred twelve thousand, one hundred one".