12516778368 has 256 divisors, whose sum is σ = 38062891200. Its totient is φ = 4098263040.

The previous prime is 12516778303. The next prime is 12516778369. The reversal of 12516778368 is 86387761521.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12516778369) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 17075730 + ... + 17076462.

Almost surely, 2^12516778368 is an apocalyptic number.

12516778368 is a gapful number since it is divisible by the number (18) 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 12516778368, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (19031445600).

12516778368 is an abundant number, since it is smaller than the sum of its proper divisors (25546112832).

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

12516778368 is an frugal number, since it uses more digits than its factorization.

12516778368 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 829 (or 799 counting only the distinct ones).

The product of its digits is 3386880, while the sum is 54.

The spelling of 12516778368 in words is "twelve billion, five hundred sixteen million, seven hundred seventy-eight thousand, three hundred sixty-eight".