205145550 has 72 divisors (see below), whose sum is σ = 564651360. Its totient is φ = 53366400.

The previous prime is 205145543. The next prime is 205145557. The reversal of 205145550 is 55541502.

205145550 is a `hidden beast` number, since 20 + 51 + 45 + 550 = 666.

205145550 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (205145543) and next prime (205145557).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205145557) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 12891 + ... + 24009.

It is an arithmetic number, because the mean of its divisors is an integer number (7842380).

Almost surely, 2^205145550 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 205145550, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (282325680).

205145550 is an abundant number, since it is smaller than the sum of its proper divisors (359505810).

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

205145550 is a wasteful number, since it uses less digits than its factorization.

205145550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11178 (or 11170 counting only the distinct ones).

The product of its (nonzero) digits is 5000, while the sum is 27.

The square root of 205145550 is about 14322.9029878723. The cubic root of 205145550 is about 589.7763683726.

The spelling of 205145550 in words is "two hundred five million, one hundred forty-five thousand, five hundred fifty".