205561427 has 4 divisors (see below), whose sum is σ = 208629576. Its totient is φ = 202493280.

The previous prime is 205561387. The next prime is 205561429. The reversal of 205561427 is 724165502.

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

It is a cyclic number.

It is not a de Polignac number, because 205561427 - 2¹⁰ = 205560403 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 205561393 and 205561402.

It is not an unprimeable number, because it can be changed into a prime (205561429) 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, 1533974 + ... + 1534107.

It is an arithmetic number, because the mean of its divisors is an integer number (52157394).

Almost surely, 2^205561427 is an apocalyptic number.

205561427 is a deficient number, since it is larger than the sum of its proper divisors (3068149).

205561427 is an equidigital number, since it uses as much as digits as its factorization.

205561427 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3068148.

The product of its (nonzero) digits is 16800, while the sum is 32.

The square root of 205561427 is about 14337.4135394080. The cubic root of 205561427 is about 590.1746366114.

The spelling of 205561427 in words is "two hundred five million, five hundred sixty-one thousand, four hundred twenty-seven".