1211221121021 has 8 divisors (see below), whose sum is σ = 1239592800864. Its totient is φ = 1182858702480.

The previous prime is 1211221121017. The next prime is 1211221121041. The reversal of 1211221121021 is 1201211221121.

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

It is a cyclic number.

It is not a de Polignac number, because 1211221121021 - 2² = 1211221121017 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1211221121041) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2050346 + ... + 2574171.

It is an arithmetic number, because the mean of its divisors is an integer number (154949100108).

Almost surely, 2^{1211221121021} is an apocalyptic number.

It is an amenable number.

1211221121021 is a deficient number, since it is larger than the sum of its proper divisors (28371679843).

1211221121021 is an equidigital number, since it uses as much as digits as its factorization.

1211221121021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4630651.

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 1211221121021 its reverse (1201211221121), we get a palindrome (2412432342142).

The spelling of 1211221121021 in words is "one trillion, two hundred eleven billion, two hundred twenty-one million, one hundred twenty-one thousand, twenty-one".