12905840640 has 768 divisors, whose sum is σ = 53552056320. Its totient is φ = 2595225600.

The previous prime is 12905840603. The next prime is 12905840669. The reversal of 12905840640 is 4604850921.

It is a tau number, because it is divible by the number of its divisors (768).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 416317425 + ... + 416317455.

It is an arithmetic number, because the mean of its divisors is an integer number (69729240).

Almost surely, 2^12905840640 is an apocalyptic number.

12905840640 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 12905840640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26776028160).

12905840640 is an abundant number, since it is smaller than the sum of its proper divisors (40646215680).

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

12905840640 is an equidigital number, since it uses as much as digits as its factorization.

12905840640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 98 (or 59 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 39.

The spelling of 12905840640 in words is "twelve billion, nine hundred five million, eight hundred forty thousand, six hundred forty".