12915571538 has 8 divisors (see below), whose sum is σ = 19551094860. Its totient is φ = 6398539920.

The previous prime is 12915571489. The next prime is 12915571561. The reversal of 12915571538 is 83517551921.

It can be written as a sum of positive squares in 2 ways, for example, as 12378120049 + 537451489 = 111257^2 + 23183^2 .

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

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 12915571492 and 12915571501.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 29622653 + ... + 29623088.

Almost surely, 2^12915571538 is an apocalyptic number.

12915571538 is a deficient number, since it is larger than the sum of its proper divisors (6635523322).

12915571538 is a wasteful number, since it uses less digits than its factorization.

12915571538 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59245852.

The product of its digits is 378000, while the sum is 47.

The spelling of 12915571538 in words is "twelve billion, nine hundred fifteen million, five hundred seventy-one thousand, five hundred thirty-eight".