7287168913921 has 8 divisors (see below), whose sum is σ = 7847779645160. Its totient is φ = 6726566650752.

The previous prime is 7287168913909. The next prime is 7287168913939. The reversal of 7287168913921 is 1293198617827.

It can be written as a sum of positive squares in 4 ways, for example, as 470135120896 + 6817033793025 = 685664^2 + 2610945^2 .

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

It is not a de Polignac number, because 7287168913921 - 2²⁵ = 7287135359489 is a prime.

It is not an unprimeable number, because it can be changed into a prime (7287168917921) 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 in 7 ways as a sum of consecutive naturals, for example, 270036 + ... + 3827173.

It is an arithmetic number, because the mean of its divisors is an integer number (980972455645).

Almost surely, 2^{7287168913921} is an apocalyptic number.

It is an amenable number.

7287168913921 is a deficient number, since it is larger than the sum of its proper divisors (560610731239).

7287168913921 is a wasteful number, since it uses less digits than its factorization.

7287168913921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4234035.

The product of its digits is 18289152, while the sum is 64.

The spelling of 7287168913921 in words is "seven trillion, two hundred eighty-seven billion, one hundred sixty-eight million, nine hundred thirteen thousand, nine hundred twenty-one".