1211221112010 has 512 divisors, whose sum is σ = 3762200494080. Its totient is φ = 242769788928.

The previous prime is 1211221111967. The next prime is 1211221112011. The reversal of 1211221112010 is 102111221121.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is not an unprimeable number, because it can be changed into a prime (1211221112011) by changing a digit.

It is a polite number, since it can be written in 255 ways as a sum of consecutive naturals, for example, 995250922 + ... + 995252138.

It is an arithmetic number, because the mean of its divisors is an integer number (7348047840).

Almost surely, 2^{1211221112010} is an apocalyptic number.

1211221112010 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1211221112010, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1881100247040).

1211221112010 is an abundant number, since it is smaller than the sum of its proper divisors (2550979382070).

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

1211221112010 is a wasteful number, since it uses less digits than its factorization.

1211221112010 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1510.

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

Adding to 1211221112010 its reverse (102111221121), we get a palindrome (1313332333131).

It can be divided in two parts, 1211221 and 112010, that added together give a palindrome (1323231).

The spelling of 1211221112010 in words is "one trillion, two hundred eleven billion, two hundred twenty-one million, one hundred twelve thousand, ten".