205403520240 has 240 divisors, whose sum is σ = 699293337600. Its totient is φ = 54023044608.

The previous prime is 205403520209. The next prime is 205403520277. The reversal of 205403520240 is 42025304502.

It is a happy number.

205403520240 is a `hidden beast` number, since 20 + 54 + 0 + 352 + 0 + 240 = 666.

It is a tau number, because it is divible by the number of its divisors (240).

It is a super-2 number, since 2×205403520240² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 89812377 + ... + 89814663.

It is an arithmetic number, because the mean of its divisors is an integer number (2913722240).

Almost surely, 2^205403520240 is an apocalyptic number.

205403520240 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 205403520240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (349646668800).

205403520240 is an abundant number, since it is smaller than the sum of its proper divisors (493889817360).

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

205403520240 is a wasteful number, since it uses less digits than its factorization.

205403520240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3964 (or 3955 counting only the distinct ones).

The product of its (nonzero) digits is 9600, while the sum is 27.

Adding to 205403520240 its reverse (42025304502), we get a palindrome (247428824742).

The spelling of 205403520240 in words is "two hundred five billion, four hundred three million, five hundred twenty thousand, two hundred forty".