205425217 has 4 divisors (see below), whose sum is σ = 206612820. Its totient is φ = 204237616.

The previous prime is 205425179. The next prime is 205425289. The reversal of 205425217 is 712524502.

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 184117761 + 21307456 = 13569^2 + 4616^2 .

It is a cyclic number.

It is not a de Polignac number, because 205425217 - 2⁷ = 205425089 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (205425817) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 593542 + ... + 593887.

It is an arithmetic number, because the mean of its divisors is an integer number (51653205).

Almost surely, 2^205425217 is an apocalyptic number.

It is an amenable number.

205425217 is a deficient number, since it is larger than the sum of its proper divisors (1187603).

205425217 is a wasteful number, since it uses less digits than its factorization.

205425217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1187602.

The product of its (nonzero) digits is 5600, while the sum is 28.

The square root of 205425217 is about 14332.6625928332. The cubic root of 205425217 is about 590.0442531204.

Adding to 205425217 its reverse (712524502), we get a palindrome (917949719).

The spelling of 205425217 in words is "two hundred five million, four hundred twenty-five thousand, two hundred seventeen".