205501720193 has 24 divisors (see below), whose sum is σ = 261157613184. Its totient is φ = 159902484000.

The previous prime is 205501720189. The next prime is 205501720231. The reversal of 205501720193 is 391027105502.

It is not a de Polignac number, because 205501720193 - 2² = 205501720189 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (205501720103) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 105896 + ... + 649782.

It is an arithmetic number, because the mean of its divisors is an integer number (10881567216).

Almost surely, 2^205501720193 is an apocalyptic number.

It is an amenable number.

205501720193 is a deficient number, since it is larger than the sum of its proper divisors (55655892991).

205501720193 is a wasteful number, since it uses less digits than its factorization.

205501720193 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 544613 (or 544606 counting only the distinct ones).

The product of its (nonzero) digits is 18900, while the sum is 35.

Adding to 205501720193 its reverse (391027105502), we get a palindrome (596528825695).

The spelling of 205501720193 in words is "two hundred five billion, five hundred one million, seven hundred twenty thousand, one hundred ninety-three".