1211221111002 has 128 divisors (see below), whose sum is σ = 2925554565120. Its totient is φ = 326968125120.

The previous prime is 1211221110919. The next prime is 1211221111049. The reversal of 1211221111002 is 2001111221121.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 214031649 + ... + 214037307.

It is an arithmetic number, because the mean of its divisors is an integer number (22855895040).

Almost surely, 2^{1211221111002} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1211221111002, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1462777282560).

1211221111002 is an abundant number, since it is smaller than the sum of its proper divisors (1714333454118).

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

1211221111002 is a wasteful number, since it uses less digits than its factorization.

1211221111002 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9568.

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

Adding to 1211221111002 its reverse (2001111221121), we get a palindrome (3212332332123).

The spelling of 1211221111002 in words is "one trillion, two hundred eleven billion, two hundred twenty-one million, one hundred eleven thousand, two".