1221021211101 has 8 divisors (see below), whose sum is σ = 1672029045984. Its totient is φ = 792013758480.

The previous prime is 1221021211099. The next prime is 1221021211103. The reversal of 1221021211101 is 1011121201221.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (1221021211099) and next prime (1221021211103).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1221021211101 - 2¹ = 1221021211099 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221021211103) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5500095435 + ... + 5500095656.

It is an arithmetic number, because the mean of its divisors is an integer number (209003630748).

Almost surely, 2^{1221021211101} is an apocalyptic number.

It is an amenable number.

1221021211101 is a deficient number, since it is larger than the sum of its proper divisors (451007834883).

1221021211101 is a wasteful number, since it uses less digits than its factorization.

1221021211101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11000191131.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 1221021211101 its reverse (1011121201221), we get a palindrome (2232142412322).

The spelling of 1221021211101 in words is "one trillion, two hundred twenty-one billion, twenty-one million, two hundred eleven thousand, one hundred one".