12825440640 has 128 divisors (see below), whose sum is σ = 45423496800. Its totient is φ = 3420112896.

The previous prime is 12825440633. The next prime is 12825440687. The reversal of 12825440640 is 4604452821.

12825440640 is a `hidden beast` number, since 1 + 2 + 8 + 2 + 5 + 4 + 4 + 0 + 640 = 666.

It is a tau number, because it is divible by the number of its divisors (128).

It is a super-2 number, since 2×12825440640² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 12825440595 and 12825440604.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 353827 + ... + 388386.

Almost surely, 2^12825440640 is an apocalyptic number.

12825440640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

12825440640 is an abundant number, since it is smaller than the sum of its proper divisors (32598056160).

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

12825440640 is an equidigital number, since it uses as much as digits as its factorization.

12825440640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 742241 (or 742223 counting only the distinct ones).

The product of its (nonzero) digits is 61440, while the sum is 36.

The spelling of 12825440640 in words is "twelve billion, eight hundred twenty-five million, four hundred forty thousand, six hundred forty".