205420555 has 4 divisors (see below), whose sum is σ = 246504672. Its totient is φ = 164336440.

The previous prime is 205420549. The next prime is 205420573. The reversal of 205420555 is 555024502.

205420555 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 555024502 = 2 ⋅277512251.

It is not a de Polignac number, because 205420555 - 2³ = 205420547 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20542051 + ... + 20542060.

It is an arithmetic number, because the mean of its divisors is an integer number (61626168).

Almost surely, 2^205420555 is an apocalyptic number.

205420555 is a deficient number, since it is larger than the sum of its proper divisors (41084117).

205420555 is an equidigital number, since it uses as much as digits as its factorization.

205420555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41084116.

The product of its (nonzero) digits is 10000, while the sum is 28.

The square root of 205420555 is about 14332.4999563928. The cubic root of 205420555 is about 590.0397895218.

The spelling of 205420555 in words is "two hundred five million, four hundred twenty thousand, five hundred fifty-five".