1211221120101 has 4 divisors (see below), whose sum is σ = 1614961493472. Its totient is φ = 807480746732.

The previous prime is 1211221120091. The next prime is 1211221120117. The reversal of 1211221120101 is 1010211221121.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1211221120101 - 2³¹ = 1209073636453 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1211221120121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 201870186681 + ... + 201870186686.

It is an arithmetic number, because the mean of its divisors is an integer number (403740373368).

Almost surely, 2^{1211221120101} is an apocalyptic number.

It is an amenable number.

1211221120101 is a deficient number, since it is larger than the sum of its proper divisors (403740373371).

1211221120101 is an equidigital number, since it uses as much as digits as its factorization.

1211221120101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 403740373370.

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

Adding to 1211221120101 its reverse (1010211221121), we get a palindrome (2221432341222).

The spelling of 1211221120101 in words is "one trillion, two hundred eleven billion, two hundred twenty-one million, one hundred twenty thousand, one hundred one".