205100001 has 24 divisors (see below), whose sum is σ = 300867840. Its totient is φ = 134620416.

The previous prime is 205099987. The next prime is 205100009. The reversal of 205100001 is 100001502.

It is a happy number.

205100001 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 205100001 - 2¹⁹ = 204575713 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (205100009) 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, 208156 + ... + 209138.

It is an arithmetic number, because the mean of its divisors is an integer number (12536160).

Almost surely, 2^205100001 is an apocalyptic number.

It is an amenable number.

205100001 is a deficient number, since it is larger than the sum of its proper divisors (95767839).

205100001 is a wasteful number, since it uses less digits than its factorization.

205100001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1325 (or 1322 counting only the distinct ones).

The product of its (nonzero) digits is 10, while the sum is 9.

The square root of 205100001 is about 14321.3128238999. The cubic root of 205100001 is about 589.7327152813.

Adding to 205100001 its reverse (100001502), we get a palindrome (305101503).

The spelling of 205100001 in words is "two hundred five million, one hundred thousand, one".