204505121315550 has 288 divisors, whose sum is σ = 571080297021696. Its totient is φ = 48369288844800.

The previous prime is 204505121315543. The next prime is 204505121315567. The reversal of 204505121315550 is 55513121505402.

It is a junction number, because it is equal to n+sod(n) for n = 204505121315499 and 204505121315508.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 692111442 + ... + 692406858.

It is an arithmetic number, because the mean of its divisors is an integer number (1982917697992).

Almost surely, 2^{204505121315550} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 204505121315550, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (285540148510848).

204505121315550 is an abundant number, since it is smaller than the sum of its proper divisors (366575175706146).

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

204505121315550 is a wasteful number, since it uses less digits than its factorization.

204505121315550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 296384 (or 296368 counting only the distinct ones).

The product of its (nonzero) digits is 150000, while the sum is 39.

The spelling of 204505121315550 in words is "two hundred four trillion, five hundred five billion, one hundred twenty-one million, three hundred fifteen thousand, five hundred fifty".