1211021001221 has 8 divisors (see below), whose sum is σ = 1213495150560. Its totient is φ = 1208547458352.

The previous prime is 1211021001217. The next prime is 1211021001241. The reversal of 1211021001221 is 1221001201121.

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 1211021001221 - 2² = 1211021001217 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1211021001196 and 1211021001205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1211021001241) 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, 3959690 + ... + 4254548.

It is an arithmetic number, because the mean of its divisors is an integer number (151686893820).

Almost surely, 2^{1211021001221} is an apocalyptic number.

It is an amenable number.

1211021001221 is a deficient number, since it is larger than the sum of its proper divisors (2474149339).

1211021001221 is an equidigital number, since it uses as much as digits as its factorization.

1211021001221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 303235.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 1211021001221 its reverse (1221001201121), we get a palindrome (2432022202342).

The spelling of 1211021001221 in words is "one trillion, two hundred eleven billion, twenty-one million, one thousand, two hundred twenty-one".