1221200021211 has 32 divisors (see below), whose sum is σ = 1731865605120. Its totient is φ = 764057145600.

The previous prime is 1221200021203. The next prime is 1221200021221. The reversal of 1221200021211 is 1121200021221.

It is not a de Polignac number, because 1221200021211 - 2³ = 1221200021203 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1221200021221) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 334996 + ... + 1598318.

It is an arithmetic number, because the mean of its divisors is an integer number (54120800160).

Almost surely, 2^{1221200021211} is an apocalyptic number.

1221200021211 is a deficient number, since it is larger than the sum of its proper divisors (510665583909).

1221200021211 is a wasteful number, since it uses less digits than its factorization.

1221200021211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1263667.

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 1221200021211 its reverse (1121200021221), we get a palindrome (2342400042432).

The spelling of 1221200021211 in words is "one trillion, two hundred twenty-one billion, two hundred million, twenty-one thousand, two hundred eleven".