204387840 has 160 divisors (see below), whose sum is σ = 726248160. Its totient is φ = 54484992.

The previous prime is 204387839. The next prime is 204387847. The reversal of 204387840 is 48783402.

It is a tau number, because it is divible by the number of its divisors (160).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 204387795 and 204387804.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (204387847) 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 15 ways as a sum of consecutive naturals, for example, 67642 + ... + 70598.

It is an arithmetic number, because the mean of its divisors is an integer number (4539051).

Almost surely, 2^204387840 is an apocalyptic number.

204387840 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 204387840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (363124080).

204387840 is an abundant number, since it is smaller than the sum of its proper divisors (521860320).

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

204387840 is an equidigital number, since it uses as much as digits as its factorization.

204387840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2989 (or 2967 counting only the distinct ones).

The product of its (nonzero) digits is 43008, while the sum is 36.

The square root of 204387840 is about 14296.4275257842. The cubic root of 204387840 is about 589.0493548441.

The spelling of 204387840 in words is "two hundred four million, three hundred eighty-seven thousand, eight hundred forty".