640569600 has 432 divisors, whose sum is σ = 2570043840. Its totient is φ = 154828800.

The previous prime is 640569599. The next prime is 640569613. The reversal of 640569600 is 6965046.

It is a happy number.

640569600 is a `hidden beast` number, since 6 + 40 + 5 + 6 + 9 + 600 = 666.

It is a tau number, because it is divible by the number of its divisors (432).

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

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1900632 + ... + 1900968.

Almost surely, 2^640569600 is an apocalyptic number.

640569600 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 640569600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1285021920).

640569600 is an abundant number, since it is smaller than the sum of its proper divisors (1929474240).

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

640569600 is a wasteful number, since it uses less digits than its factorization.

640569600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 383 (or 358 counting only the distinct ones).

The product of its (nonzero) digits is 38880, while the sum is 36.

The square root of 640569600 is about 25309.4764860911. The cubic root of 640569600 is about 862.0294597878.

The spelling of 640569600 in words is "six hundred forty million, five hundred sixty-nine thousand, six hundred".