12642561699840 has 1248 divisors, whose sum is σ = 46547266461696. Its totient is φ = 3290793246720.

The previous prime is 12642561699829. The next prime is 12642561699863. The reversal of 12642561699840 is 4899616524621.

12642561699840 is a `hidden beast` number, since 1 + 2 + 6 + 4 + 2 + 5 + 616 + 9 + 9 + 8 + 4 + 0 = 666.

It is a super-2 number, since 2×12642561699840² (a number of 27 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 52458762120 + ... + 52458762360.

It is an arithmetic number, because the mean of its divisors is an integer number (37297489152).

Almost surely, 2^{12642561699840} is an apocalyptic number.

12642561699840 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 12642561699840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23273633230848).

12642561699840 is an abundant number, since it is smaller than the sum of its proper divisors (33904704761856).

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

12642561699840 is an equidigital number, since it uses as much as digits as its factorization.

12642561699840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 495 (or 461 counting only the distinct ones).

The product of its (nonzero) digits is 44789760, while the sum is 63.

The spelling of 12642561699840 in words is "twelve trillion, six hundred forty-two billion, five hundred sixty-one million, six hundred ninety-nine thousand, eight hundred forty".