640353600 has 378 divisors, whose sum is σ = 2402129054. Its totient is φ = 167961600.

The previous prime is 640353587. The next prime is 640353613. The reversal of 640353600 is 6353046.

640353600 is a `hidden beast` number, since 6 + 4 + 0 + 3 + 53 + 600 = 666.

It is an interprime number because it is at equal distance from previous prime (640353587) and next prime (640353613).

It can be written as a sum of positive squares in 3 ways, for example, as 1679616 + 638673984 = 1296^2 + 25272^2 .

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 53 ways as a sum of consecutive naturals, for example, 10497570 + ... + 10497630.

Almost surely, 2^640353600 is an apocalyptic number.

640353600 is a gapful number since it is divisible by the number (60) 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 640353600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1201064527).

640353600 is an abundant number, since it is smaller than the sum of its proper divisors (1761775454).

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

640353600 is an frugal number, since it uses more digits than its factorization.

640353600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 107 (or 71 counting only the distinct ones).

The product of its (nonzero) digits is 6480, while the sum is 27.

The square root of 640353600 is about 25305.2089499376. The cubic root of 640353600 is about 861.9325568148.

The spelling of 640353600 in words is "six hundred forty million, three hundred fifty-three thousand, six hundred".