205551243523 has 16 divisors (see below), whose sum is σ = 219864153600. Its totient is φ = 191487044736.

The previous prime is 205551243509. The next prime is 205551243533. The reversal of 205551243523 is 325342155502.

It is not a de Polignac number, because 205551243523 - 2¹⁷ = 205551112451 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (205551243533) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3647386 + ... + 3703312.

It is an arithmetic number, because the mean of its divisors is an integer number (13741509600).

Almost surely, 2^205551243523 is an apocalyptic number.

205551243523 is a deficient number, since it is larger than the sum of its proper divisors (14312910077).

205551243523 is a wasteful number, since it uses less digits than its factorization.

205551243523 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 58146.

The product of its (nonzero) digits is 180000, while the sum is 37.

The spelling of 205551243523 in words is "two hundred five billion, five hundred fifty-one million, two hundred forty-three thousand, five hundred twenty-three".