121212122100 has 144 divisors (see below), whose sum is σ = 361739222208. Its totient is φ = 31313986560.

The previous prime is 121212122089. The next prime is 121212122107. The reversal of 121212122100 is 1221212121.

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

It is a self number, because there is not a number n which added to its sum of digits gives 121212122100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121212122107) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2562867 + ... + 2609733.

It is an arithmetic number, because the mean of its divisors is an integer number (2512077932).

Almost surely, 2^121212122100 is an apocalyptic number.

121212122100 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 121212122100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (180869611104).

121212122100 is an abundant number, since it is smaller than the sum of its proper divisors (240527100108).

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

121212122100 is a wasteful number, since it uses less digits than its factorization.

121212122100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47154 (or 47147 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 121212122100 its reverse (1221212121), we get a palindrome (122433334221).

The spelling of 121212122100 in words is "one hundred twenty-one billion, two hundred twelve million, one hundred twenty-two thousand, one hundred".