205115840 has 168 divisors, whose sum is σ = 544799520. Its totient is φ = 73328640.

The previous prime is 205115839. The next prime is 205115851. The reversal of 205115840 is 48511502.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6616625 + ... + 6616655.

Almost surely, 2^205115840 is an apocalyptic number.

205115840 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 205115840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (272399760).

205115840 is an abundant number, since it is smaller than the sum of its proper divisors (339683680).

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

205115840 is a wasteful number, since it uses less digits than its factorization.

205115840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 131 (or 90 counting only the distinct ones).

The product of its (nonzero) digits is 1600, while the sum is 26.

The square root of 205115840 is about 14321.8658002371. The cubic root of 205115840 is about 589.7478957396.

The spelling of 205115840 in words is "two hundred five million, one hundred fifteen thousand, eight hundred forty".