1211111220204 has 36 divisors (see below), whose sum is σ = 3061670670240. Its totient is φ = 403670688480.

The previous prime is 1211111220167. The next prime is 1211111220269. The reversal of 1211111220204 is 4020221111121.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 929332 + ... + 1812699.

Almost surely, 2^{1211111220204} is an apocalyptic number.

It is an amenable number.

1211111220204 is an abundant number, since it is smaller than the sum of its proper divisors (1850559450036).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1211111220204 is a wasteful number, since it uses less digits than its factorization.

1211111220204 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2754310 (or 2754305 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 1211111220204 its reverse (4020221111121), we get a palindrome (5231332331325).

The spelling of 1211111220204 in words is "one trillion, two hundred eleven billion, one hundred eleven million, two hundred twenty thousand, two hundred four".