33121221100 has 108 divisors (see below), whose sum is σ = 80493098112. Its totient is φ = 11816604800.

The previous prime is 33121221079. The next prime is 33121221109. The reversal of 33121221100 is 112212133.

It is not an unprimeable number, because it can be changed into a prime (33121221109) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 615477 + ... + 667123.

It is an arithmetic number, because the mean of its divisors is an integer number (745306464).

Almost surely, 2^33121221100 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 33121221100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40246549056).

33121221100 is an abundant number, since it is smaller than the sum of its proper divisors (47371877012).

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

33121221100 is a wasteful number, since it uses less digits than its factorization.

33121221100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51736 (or 51718 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 16.

Adding to 33121221100 its reverse (112212133), we get a palindrome (33233433233).

The spelling of 33121221100 in words is "thirty-three billion, one hundred twenty-one million, two hundred twenty-one thousand, one hundred".