12121515121100 has 72 divisors (see below), whose sum is σ = 32794208203008. Its totient is φ = 3778134580800.

The previous prime is 12121515121013. The next prime is 12121515121153. The reversal of 12121515121100 is 112151512121.

It is a super-2 number, since 2×12121515121100² (a number of 27 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 787103672 + ... + 787119071.

Almost surely, 2^{12121515121100} is an apocalyptic number.

12121515121100 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

12121515121100 is an abundant number, since it is smaller than the sum of its proper divisors (20672693081908).

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

12121515121100 is a wasteful number, since it uses less digits than its factorization.

12121515121100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1574222775 (or 1574222768 counting only the distinct ones).

The product of its (nonzero) digits is 200, while the sum is 23.

Adding to 12121515121100 its reverse (112151512121), we get a palindrome (12233666633221).

The spelling of 12121515121100 in words is "twelve trillion, one hundred twenty-one billion, five hundred fifteen million, one hundred twenty-one thousand, one hundred".