205139726086 has 4 divisors (see below), whose sum is σ = 307709589132. Its totient is φ = 102569863042.

The previous prime is 205139726083. The next prime is 205139726093. The reversal of 205139726086 is 680627931502.

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

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205139726083) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 51284931520 + ... + 51284931523.

It is an arithmetic number, because the mean of its divisors is an integer number (76927397283).

Almost surely, 2^205139726086 is an apocalyptic number.

205139726086 is a deficient number, since it is larger than the sum of its proper divisors (102569863046).

205139726086 is a wasteful number, since it uses less digits than its factorization.

205139726086 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 102569863045.

The product of its (nonzero) digits is 1088640, while the sum is 49.

It can be divided in two parts, 205139 and 726086, that added together give a square (931225 = 965²).

The spelling of 205139726086 in words is "two hundred five billion, one hundred thirty-nine million, seven hundred twenty-six thousand, eighty-six".