1221200111211 has 16 divisors (see below), whose sum is σ = 1632608729088. Its totient is φ = 811963152000.

The previous prime is 1221200111167. The next prime is 1221200111233. The reversal of 1221200111211 is 1121110021221.

It is a happy number.

It is not a de Polignac number, because 1221200111211 - 2¹⁷ = 1221199980139 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1221200111251) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7141926 + ... + 7310916.

It is an arithmetic number, because the mean of its divisors is an integer number (102038045568).

Almost surely, 2^{1221200111211} is an apocalyptic number.

1221200111211 is a deficient number, since it is larger than the sum of its proper divisors (411408617877).

1221200111211 is a wasteful number, since it uses less digits than its factorization.

1221200111211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 175402.

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

Adding to 1221200111211 its reverse (1121110021221), we get a palindrome (2342310132432).

The spelling of 1221200111211 in words is "one trillion, two hundred twenty-one billion, two hundred million, one hundred eleven thousand, two hundred eleven".