1211221111000 has 32 divisors (see below), whose sum is σ = 2834257402080. Its totient is φ = 484488444000.

The previous prime is 1211221110919. The next prime is 1211221111049. The reversal of 1211221111000 is 1111221121.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 605609556 + ... + 605611555.

It is an arithmetic number, because the mean of its divisors is an integer number (88570543815).

Almost surely, 2^{1211221111000} is an apocalyptic number.

1211221111000 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1211221111000 is an abundant number, since it is smaller than the sum of its proper divisors (1623036291080).

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

1211221111000 is a wasteful number, since it uses less digits than its factorization.

1211221111000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1211221132 (or 1211221118 counting only the distinct ones).

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

Adding to 1211221111000 its reverse (1111221121), we get a palindrome (1212332332121).

The spelling of 1211221111000 in words is "one trillion, two hundred eleven billion, two hundred twenty-one million, one hundred eleven thousand".