12561605615 has 8 divisors (see below), whose sum is σ = 16233459648. Its totient is φ = 9276262560.

The previous prime is 12561605579. The next prime is 12561605627. The reversal of 12561605615 is 51650616521.

It is a happy number.

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

It is not a de Polignac number, because 12561605615 - 2⁸ = 12561605359 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 96627671 + ... + 96627800.

It is an arithmetic number, because the mean of its divisors is an integer number (2029182456).

Almost surely, 2^12561605615 is an apocalyptic number.

12561605615 is a deficient number, since it is larger than the sum of its proper divisors (3671854033).

12561605615 is a wasteful number, since it uses less digits than its factorization.

12561605615 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 193255489.

The product of its (nonzero) digits is 54000, while the sum is 38.

The spelling of 12561605615 in words is "twelve billion, five hundred sixty-one million, six hundred five thousand, six hundred fifteen".