12891512500 has 72 divisors (see below), whose sum is σ = 28799656704. Its totient is φ = 5046660000.

The previous prime is 12891512461. The next prime is 12891512503. The reversal of 12891512500 is 521519821.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12891512503) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 576529 + ... + 598471.

It is an arithmetic number, because the mean of its divisors is an integer number (399995232).

Almost surely, 2^12891512500 is an apocalyptic number.

12891512500 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 12891512500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14399828352).

12891512500 is an abundant number, since it is smaller than the sum of its proper divisors (15908144204).

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

12891512500 is an equidigital number, since it uses as much as digits as its factorization.

12891512500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22019 (or 21997 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 34.

The spelling of 12891512500 in words is "twelve billion, eight hundred ninety-one million, five hundred twelve thousand, five hundred".