7287171727861 has 4 divisors (see below), whose sum is σ = 7327432345324. Its totient is φ = 7246911110400.

The previous prime is 7287171727811. The next prime is 7287171727867. The reversal of 7287171727861 is 1687271717827.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 3878418196900 + 3408753530961 = 1969370^2 + 1846281^2 .

It is a cyclic number.

It is not a de Polignac number, because 7287171727861 - 2¹³ = 7287171719669 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 7287171727793 and 7287171727802.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7287171727867) 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 3 ways as a sum of consecutive naturals, for example, 20130308460 + ... + 20130308821.

It is an arithmetic number, because the mean of its divisors is an integer number (1831858086331).

Almost surely, 2^{7287171727861} is an apocalyptic number.

It is an amenable number.

7287171727861 is a deficient number, since it is larger than the sum of its proper divisors (40260617463).

7287171727861 is a wasteful number, since it uses less digits than its factorization.

7287171727861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40260617462.

The product of its digits is 25815552, while the sum is 64.

The spelling of 7287171727861 in words is "seven trillion, two hundred eighty-seven billion, one hundred seventy-one million, seven hundred twenty-seven thousand, eight hundred sixty-one".