640208000 has 64 divisors (see below), whose sum is σ = 1591756920. Its totient is φ = 256076800.

The previous prime is 640207979. The next prime is 640208011. The reversal of 640208000 is 802046.

It can be written as a sum of positive squares in 4 ways, for example, as 167754304 + 472453696 = 12952^2 + 21736^2 .

It is a tau number, because it is divible by the number of its divisors (64).

It is a Harshad number since it is a multiple of its sum of digits (20).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4007 + ... + 36006.

Almost surely, 2^640208000 is an apocalyptic number.

It is an amenable number.

640208000 is an abundant number, since it is smaller than the sum of its proper divisors (951548920).

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

640208000 is an equidigital number, since it uses as much as digits as its factorization.

640208000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40042 (or 40020 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 20.

The square root of 640208000 is about 25302.3319083439. The cubic root of 640208000 is about 861.8672247373.

The spelling of 640208000 in words is "six hundred forty million, two hundred eight thousand".