12615997981440 has 3456 divisors, whose sum is σ = 55046506798080. Its totient is φ = 2437624627200.

The previous prime is 12615997981369. The next prime is 12615997981453. The reversal of 12615997981440 is 4418979951621.

It is an unprimeable number.

It is a polite number, since it can be written in 383 ways as a sum of consecutive naturals, for example, 151999975639 + ... + 151999975721.

It is an arithmetic number, because the mean of its divisors is an integer number (15927808680).

Almost surely, 2^{12615997981440} is an apocalyptic number.

12615997981440 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 12615997981440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27523253399040).

12615997981440 is an abundant number, since it is smaller than the sum of its proper divisors (42430508816640).

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

12615997981440 is a wasteful number, since it uses less digits than its factorization.

12615997981440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 259 (or 238 counting only the distinct ones).

The product of its (nonzero) digits is 39191040, while the sum is 66.

The spelling of 12615997981440 in words is "twelve trillion, six hundred fifteen billion, nine hundred ninety-seven million, nine hundred eighty-one thousand, four hundred forty".