12121321100 has 108 divisors (see below), whose sum is σ = 30737657664. Its totient is φ = 4136872320.

The previous prime is 12121321097. The next prime is 12121321109. The reversal of 12121321100 is 112312121.

It is a Harshad number since it is a multiple of its sum of digits (14).

It is not an unprimeable number, because it can be changed into a prime (12121321109) 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, 1087154 + ... + 1098246.

Almost surely, 2^12121321100 is an apocalyptic number.

12121321100 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 12121321100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (15368828832).

12121321100 is an abundant number, since it is smaller than the sum of its proper divisors (18616336564).

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

12121321100 is a wasteful number, since it uses less digits than its factorization.

12121321100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11344 (or 11330 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 14.

Adding to 12121321100 its reverse (112312121), we get a palindrome (12233633221).

The spelling of 12121321100 in words is "twelve billion, one hundred twenty-one million, three hundred twenty-one thousand, one hundred".