12640205541 has 8 divisors (see below), whose sum is σ = 16854141024. Its totient is φ = 8426536880.

The previous prime is 12640205533. The next prime is 12640205569. The reversal of 12640205541 is 14550204621.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 12640205541 - 2³ = 12640205533 is a prime.

It is a super-2 number, since 2×12640205541² (a number of 21 digits) contains 22 as substring.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 12640205499 and 12640205508.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12640205441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 112990 + ... + 195056.

It is an arithmetic number, because the mean of its divisors is an integer number (2106767628).

Almost surely, 2^12640205541 is an apocalyptic number.

It is an amenable number.

12640205541 is a deficient number, since it is larger than the sum of its proper divisors (4213935483).

12640205541 is an equidigital number, since it uses as much as digits as its factorization.

12640205541 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 133411.

The product of its (nonzero) digits is 9600, while the sum is 30.

The spelling of 12640205541 in words is "twelve billion, six hundred forty million, two hundred five thousand, five hundred forty-one".