205123554001 has 4 divisors (see below), whose sum is σ = 205212856932. Its totient is φ = 205034251072.

The previous prime is 205123553983. The next prime is 205123554007. The reversal of 205123554001 is 100455321502.

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

It can be written as a sum of positive squares in 2 ways, for example, as 162098838225 + 43024715776 = 402615^2 + 207424^2 .

It is a cyclic number.

It is not a de Polignac number, because 205123554001 - 2¹¹ = 205123551953 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (205123554007) 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 3 ways as a sum of consecutive naturals, for example, 44648020 + ... + 44652613.

It is an arithmetic number, because the mean of its divisors is an integer number (51303214233).

Almost surely, 2^205123554001 is an apocalyptic number.

It is an amenable number.

205123554001 is a deficient number, since it is larger than the sum of its proper divisors (89302931).

205123554001 is an equidigital number, since it uses as much as digits as its factorization.

205123554001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 89302930.

The product of its (nonzero) digits is 6000, while the sum is 28.

Adding to 205123554001 its reverse (100455321502), we get a palindrome (305578875503).

The spelling of 205123554001 in words is "two hundred five billion, one hundred twenty-three million, five hundred fifty-four thousand, one".