121111211221000 has 768 divisors, whose sum is σ = 392744542095360. Its totient is φ = 33995174400000.

The previous prime is 121111211220971. The next prime is 121111211221009. The reversal of 121111211221000 is 122112111121.

It is not an unprimeable number, because it can be changed into a prime (121111211221009) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 451316865 + ... + 451585135.

It is an arithmetic number, because the mean of its divisors is an integer number (511386122520).

Almost surely, 2^{121111211221000} is an apocalyptic number.

121111211221000 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 121111211221000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (196372271047680).

121111211221000 is an abundant number, since it is smaller than the sum of its proper divisors (271633330874360).

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

121111211221000 is a wasteful number, since it uses less digits than its factorization.

121111211221000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 268375 (or 268350 counting only the distinct ones).

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

Adding to 121111211221000 its reverse (122112111121), we get a palindrome (121233323332121).

The spelling of 121111211221000 in words is "one hundred twenty-one trillion, one hundred eleven billion, two hundred eleven million, two hundred twenty-one thousand".