217973538135 has 48 divisors (see below), whose sum is σ = 392080905216. Its totient is φ = 116173411488.

The previous prime is 217973538131. The next prime is 217973538163. The reversal of 217973538135 is 531835379712.

It is a happy number.

217973538135 is a `hidden beast` number, since 2 + 1 + 7 + 9 + 73 + 538 + 1 + 35 = 666.

217973538135 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 217973538135 - 2² = 217973538131 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (217973538131) 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 47 ways as a sum of consecutive naturals, for example, 1746382 + ... + 1867028.

It is an arithmetic number, because the mean of its divisors is an integer number (8168352192).

Almost surely, 2^217973538135 is an apocalyptic number.

217973538135 is a deficient number, since it is larger than the sum of its proper divisors (174107367081).

217973538135 is a wasteful number, since it uses less digits than its factorization.

217973538135 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 122154 (or 122142 counting only the distinct ones).

The product of its digits is 4762800, while the sum is 54.

The spelling of 217973538135 in words is "two hundred seventeen billion, nine hundred seventy-three million, five hundred thirty-eight thousand, one hundred thirty-five".