204997905979775 has 6 divisors (see below), whose sum is σ = 254197403414952. Its totient is φ = 163998324783800.

The previous prime is 204997905979771. The next prime is 204997905979787. The reversal of 204997905979775 is 577979509799402.

It is a happy number.

It is not a de Polignac number, because 204997905979775 - 2² = 204997905979771 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (204997905979771) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4099958119571 + ... + 4099958119620.

It is an arithmetic number, because the mean of its divisors is an integer number (42366233902492).

Almost surely, 2^{204997905979775} is an apocalyptic number.

204997905979775 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

204997905979775 is a deficient number, since it is larger than the sum of its proper divisors (49199497435177).

204997905979775 is an equidigital number, since it uses as much as digits as its factorization.

204997905979775 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8199916239201 (or 8199916239196 counting only the distinct ones).

The product of its (nonzero) digits is 28355329800, while the sum is 89.

The spelling of 204997905979775 in words is "two hundred four trillion, nine hundred ninety-seven billion, nine hundred five million, nine hundred seventy-nine thousand, seven hundred seventy-five".