204684226561 has 4 divisors (see below), whose sum is σ = 208153450800. Its totient is φ = 201215002324.

The previous prime is 204684226469. The next prime is 204684226613. The reversal of 204684226561 is 165622486402.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 165622486402 = 2 ⋅82811243201.

It is a cyclic number.

It is not a de Polignac number, because 204684226561 - 2¹⁵ = 204684193793 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (204684266561) 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, 1734612031 + ... + 1734612148.

It is an arithmetic number, because the mean of its divisors is an integer number (52038362700).

Almost surely, 2^204684226561 is an apocalyptic number.

It is an amenable number.

204684226561 is a deficient number, since it is larger than the sum of its proper divisors (3469224239).

204684226561 is an equidigital number, since it uses as much as digits as its factorization.

204684226561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3469224238.

The product of its (nonzero) digits is 1105920, while the sum is 46.

The spelling of 204684226561 in words is "two hundred four billion, six hundred eighty-four million, two hundred twenty-six thousand, five hundred sixty-one".