640067000 has 128 divisors (see below), whose sum is σ = 1655821440. Its totient is φ = 230348800.

The previous prime is 640066979. The next prime is 640067039. The reversal of 640067000 is 760046.

It is a Harshad number since it is a multiple of its sum of digits (23).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 390182 + ... + 391818.

It is an arithmetic number, because the mean of its divisors is an integer number (12936105).

Almost surely, 2^640067000 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 640067000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (827910720).

640067000 is an abundant number, since it is smaller than the sum of its proper divisors (1015754440).

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

640067000 is a wasteful number, since it uses less digits than its factorization.

640067000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1698 (or 1684 counting only the distinct ones).

The product of its (nonzero) digits is 1008, while the sum is 23.

The square root of 640067000 is about 25299.5454504621. The cubic root of 640067000 is about 861.8039472810.

The spelling of 640067000 in words is "six hundred forty million, sixty-seven thousand".