206501172105 has 16 divisors (see below), whose sum is σ = 331118593344. Its totient is φ = 109895052480.

The previous prime is 206501172103. The next prime is 206501172109. The reversal of 206501172105 is 501271105602.

It is not a de Polignac number, because 206501172105 - 2¹ = 206501172103 is a prime.

It is not an unprimeable number, because it can be changed into a prime (206501172103) 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 15 ways as a sum of consecutive naturals, for example, 14924479 + ... + 14938308.

It is an arithmetic number, because the mean of its divisors is an integer number (20694912084).

Almost surely, 2^206501172105 is an apocalyptic number.

It is an amenable number.

206501172105 is a deficient number, since it is larger than the sum of its proper divisors (124617421239).

206501172105 is a wasteful number, since it uses less digits than its factorization.

206501172105 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29863256.

The product of its (nonzero) digits is 4200, while the sum is 30.

Adding to 206501172105 its reverse (501271105602), we get a palindrome (707772277707).

The spelling of 206501172105 in words is "two hundred six billion, five hundred one million, one hundred seventy-two thousand, one hundred five".