205640608 has 48 divisors (see below), whose sum is σ = 436133376. Its totient is φ = 95166720.

The previous prime is 205640587. The next prime is 205640609. The reversal of 205640608 is 806046502.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is a self number, because there is not a number n which added to its sum of digits gives 205640608.

It is not an unprimeable number, because it can be changed into a prime (205640609) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18310 + ... + 27322.

It is an arithmetic number, because the mean of its divisors is an integer number (9086112).

Almost surely, 2^205640608 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 205640608, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (218066688).

205640608 is an abundant number, since it is smaller than the sum of its proper divisors (230492768).

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

205640608 is a wasteful number, since it uses less digits than its factorization.

205640608 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9077 (or 9069 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 31.

The square root of 205640608 is about 14340.1746153943. The cubic root of 205640608 is about 590.2504040998.

The spelling of 205640608 in words is "two hundred five million, six hundred forty thousand, six hundred eight".