1211211121000 has 128 divisors (see below), whose sum is σ = 3001668658560. Its totient is φ = 455876736000.

The previous prime is 1211211120979. The next prime is 1211211121033. The reversal of 1211211121000 is 1211121121.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 129246315 + ... + 129255685.

It is an arithmetic number, because the mean of its divisors is an integer number (23450536395).

Almost surely, 2^{1211211121000} is an apocalyptic number.

1211211121000 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1211211121000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1500834329280).

1211211121000 is an abundant number, since it is smaller than the sum of its proper divisors (1790457537560).

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

1211211121000 is a wasteful number, since it uses less digits than its factorization.

1211211121000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17012 (or 16998 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 13.

Adding to 1211211121000 its reverse (1211121121), we get a palindrome (1212422242121).

The spelling of 1211211121000 in words is "one trillion, two hundred eleven billion, two hundred eleven million, one hundred twenty-one thousand".