12105121900 has 36 divisors (see below), whose sum is σ = 26279816248. Its totient is φ = 4839891840.

The previous prime is 12105121883. The next prime is 12105121907. The reversal of 12105121900 is 912150121.

It is a super-2 number, since 2×12105121900² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (12105121907) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 208912 + ... + 260488.

Almost surely, 2^12105121900 is an apocalyptic number.

12105121900 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

12105121900 is an abundant number, since it is smaller than the sum of its proper divisors (14174694348).

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

12105121900 is a wasteful number, since it uses less digits than its factorization.

12105121900 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53938 (or 53931 counting only the distinct ones).

The product of its (nonzero) digits is 180, while the sum is 22.

The spelling of 12105121900 in words is "twelve billion, one hundred five million, one hundred twenty-one thousand, nine hundred".