205580640 has 96 divisors (see below), whose sum is σ = 659879136. Its totient is φ = 53780480.

The previous prime is 205580633. The next prime is 205580657. The reversal of 205580640 is 46085502.

It is a tau number, because it is divible by the number of its divisors (96).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 205580598 and 205580607.

It is a congruent number.

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, 21400 + ... + 29480.

It is an arithmetic number, because the mean of its divisors is an integer number (6873741).

Almost surely, 2^205580640 is an apocalyptic number.

205580640 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 205580640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (329939568).

205580640 is an abundant number, since it is smaller than the sum of its proper divisors (454298496).

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

205580640 is a wasteful number, since it uses less digits than its factorization.

205580640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8152 (or 8144 counting only the distinct ones).

The product of its (nonzero) digits is 9600, while the sum is 30.

The square root of 205580640 is about 14338.0835539482. The cubic root of 205580640 is about 590.1930231220.

The spelling of 205580640 in words is "two hundred five million, five hundred eighty thousand, six hundred forty".