15687449561 has 8 divisors (see below), whose sum is σ = 18365794944. Its totient is φ = 13118424480.

The previous prime is 15687449543. The next prime is 15687449563. The reversal of 15687449561 is 16594478651.

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

It is not a de Polignac number, because 15687449561 - 2⁶ = 15687449497 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 15687449497 and 15687449506.

It is not an unprimeable number, because it can be changed into a prime (15687449563) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 27329765 + ... + 27330338.

It is an arithmetic number, because the mean of its divisors is an integer number (2295724368).

Almost surely, 2^15687449561 is an apocalyptic number.

It is an amenable number.

15687449561 is a deficient number, since it is larger than the sum of its proper divisors (2678345383).

15687449561 is an equidigital number, since it uses as much as digits as its factorization.

15687449561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54660151.

The product of its digits is 7257600, while the sum is 56.

The spelling of 15687449561 in words is "fifteen billion, six hundred eighty-seven million, four hundred forty-nine thousand, five hundred sixty-one".