1211200001221 has 8 divisors (see below), whose sum is σ = 1384401427904. Its totient is φ = 1038041788320.

The previous prime is 1211200001203. The next prime is 1211200001269. The reversal of 1211200001221 is 1221000021121.

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 1211200001221 - 2¹⁵ = 1211199968453 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 (1211200001021) 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, 10743360 + ... + 10855513.

It is an arithmetic number, because the mean of its divisors is an integer number (173050178488).

Almost surely, 2^{1211200001221} is an apocalyptic number.

It is an amenable number.

1211200001221 is a deficient number, since it is larger than the sum of its proper divisors (173201426683).

1211200001221 is an equidigital number, since it uses as much as digits as its factorization.

1211200001221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21606891.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 1211200001221 its reverse (1221000021121), we get a palindrome (2432200022342).

The spelling of 1211200001221 in words is "one trillion, two hundred eleven billion, two hundred million, one thousand, two hundred twenty-one".