640429504 has 224 divisors, whose sum is σ = 1638604800. Its totient is φ = 243855360.

The previous prime is 640429501. The next prime is 640429507. The reversal of 640429504 is 405924046.

It is an interprime number because it is at equal distance from previous prime (640429501) and next prime (640429507).

It is a self number, because there is not a number n which added to its sum of digits gives 640429504.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640429501) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5042689 + ... + 5042815.

It is an arithmetic number, because the mean of its divisors is an integer number (7315200).

Almost surely, 2^640429504 is an apocalyptic number.

640429504 is a gapful number since it is divisible by the number (64) 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 640429504, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (819302400).

640429504 is an abundant number, since it is smaller than the sum of its proper divisors (998175296).

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

640429504 is a wasteful number, since it uses less digits than its factorization.

640429504 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 211 (or 201 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 34.

The square root of 640429504 is about 25306.7086757642. The cubic root of 640429504 is about 861.9666117203.

The spelling of 640429504 in words is "six hundred forty million, four hundred twenty-nine thousand, five hundred four".