15871571561 has 2 divisors, whose sum is σ = 15871571562. Its totient is φ = 15871571560.

The previous prime is 15871571543. The next prime is 15871571581. The reversal of 15871571561 is 16517517851.

15871571561 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13893101161 + 1978470400 = 117869^2 + 44480^2 .

It is an emirp because it is prime and its reverse (16517517851) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 15871571561 - 2¹⁴ = 15871555177 is a prime.

It is not a weakly prime, because it can be changed into another prime (15871571581) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7935785780 + 7935785781.

It is an arithmetic number, because the mean of its divisors is an integer number (7935785781).

Almost surely, 2^15871571561 is an apocalyptic number.

It is an amenable number.

15871571561 is a deficient number, since it is larger than the sum of its proper divisors (1).

15871571561 is an equidigital number, since it uses as much as digits as its factorization.

15871571561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 294000, while the sum is 47.

The spelling of 15871571561 in words is "fifteen billion, eight hundred seventy-one million, five hundred seventy-one thousand, five hundred sixty-one".