205145520 has 80 divisors (see below), whose sum is σ = 637459200. Its totient is φ = 54575872.

The previous prime is 205145519. The next prime is 205145543. The reversal of 205145520 is 25541502.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 143047 + ... + 144473.

It is an arithmetic number, because the mean of its divisors is an integer number (7968240).

Almost surely, 2^205145520 is an apocalyptic number.

205145520 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 205145520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (318729600).

205145520 is an abundant number, since it is smaller than the sum of its proper divisors (432313680).

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

205145520 is a wasteful number, since it uses less digits than its factorization.

205145520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2042 (or 2036 counting only the distinct ones).

The product of its (nonzero) digits is 2000, while the sum is 24.

The square root of 205145520 is about 14322.9019405985. The cubic root of 205145520 is about 589.7763396235.

The spelling of 205145520 in words is "two hundred five million, one hundred forty-five thousand, five hundred twenty".