204206640 has 80 divisors (see below), whose sum is σ = 690598656. Its totient is φ = 49504000.

The previous prime is 204206593. The next prime is 204206657. The reversal of 204206640 is 46602402.

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 a self number, because there is not a number n which added to its sum of digits gives 204206640.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 36036 + ... + 41315.

Almost surely, 2^204206640 is an apocalyptic number.

204206640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

204206640 is an abundant number, since it is smaller than the sum of its proper divisors (486392016).

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

204206640 is a wasteful number, since it uses less digits than its factorization.

204206640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77378 (or 77372 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 24.

The square root of 204206640 is about 14290.0888730616. The cubic root of 204206640 is about 588.8752295132.

The spelling of 204206640 in words is "two hundred four million, two hundred six thousand, six hundred forty".