205404115321551 has 32 divisors (see below), whose sum is σ = 282805192990720. Its totient is φ = 132472640505600.

The previous prime is 205404115321519. The next prime is 205404115321607. The reversal of 205404115321551 is 155123511404502.

It is not a de Polignac number, because 205404115321551 - 2⁵ = 205404115321519 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205404115321051) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 6048218211 + ... + 6048252171.

It is an arithmetic number, because the mean of its divisors is an integer number (8837662280960).

Almost surely, 2^{205404115321551} is an apocalyptic number.

205404115321551 is a deficient number, since it is larger than the sum of its proper divisors (77401077669169).

205404115321551 is a wasteful number, since it uses less digits than its factorization.

205404115321551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54727.

The product of its (nonzero) digits is 120000, while the sum is 39.

The spelling of 205404115321551 in words is "two hundred five trillion, four hundred four billion, one hundred fifteen million, three hundred twenty-one thousand, five hundred fifty-one".