217315138727 has 4 divisors (see below), whose sum is σ = 218407174800. Its totient is φ = 216223102656.

The previous prime is 217315138697. The next prime is 217315138753. The reversal of 217315138727 is 727831513712.

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

It is a cyclic number.

It is not a de Polignac number, because 217315138727 - 2¹⁰ = 217315137703 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (217315138127) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 546017738 + ... + 546018135.

It is an arithmetic number, because the mean of its divisors is an integer number (54601793700).

Almost surely, 2^217315138727 is an apocalyptic number.

217315138727 is a deficient number, since it is larger than the sum of its proper divisors (1092036073).

217315138727 is a wasteful number, since it uses less digits than its factorization.

217315138727 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1092036072.

The product of its digits is 493920, while the sum is 47.

The spelling of 217315138727 in words is "two hundred seventeen billion, three hundred fifteen million, one hundred thirty-eight thousand, seven hundred twenty-seven".