205420 has 12 divisors (see below), whose sum is σ = 431424. Its totient is φ = 82160.

The previous prime is 205417. The next prime is 205421. The reversal of 205420 is 24502.

205420 = T₁₇₉ + T₁₈₀ + ... + T₁₉₀.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 205420.

It is not an unprimeable number, because it can be changed into a prime (205421) 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, 5116 + ... + 5155.

It is an arithmetic number, because the mean of its divisors is an integer number (35952).

2²⁰⁵⁴²⁰ is an apocalyptic number.

205420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

205420 is an abundant number, since it is smaller than the sum of its proper divisors (226004).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

205420 is a wasteful number, since it uses less digits than its factorization.

205420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10280 (or 10278 counting only the distinct ones).

The product of its (nonzero) digits is 80, while the sum is 13.

The square root of 205420 is about 453.2328319970. The cubic root of 205420 is about 59.0039258137.

Adding to 205420 its reverse (24502), we get a palindrome (229922).

It can be divided in two parts, 205 and 420, that added together give a 4-th power (625 = 5⁴).

The spelling of 205420 in words is "two hundred five thousand, four hundred twenty".