640383744 has 576 divisors, whose sum is σ = 2472422400. Its totient is φ = 144506880.

The previous prime is 640383743. The next prime is 640383749. The reversal of 640383744 is 447383046.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640383743) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 37669624 + ... + 37669640.

It is an arithmetic number, because the mean of its divisors is an integer number (4292400).

Almost surely, 2^640383744 is an apocalyptic number.

640383744 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 640383744, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1236211200).

640383744 is an abundant number, since it is smaller than the sum of its proper divisors (1832038656).

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

640383744 is a wasteful number, since it uses less digits than its factorization.

640383744 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81 (or 53 counting only the distinct ones).

The product of its (nonzero) digits is 193536, while the sum is 39.

The square root of 640383744 is about 25305.8045515253. The cubic root of 640383744 is about 861.9460814712.

The spelling of 640383744 in words is "six hundred forty million, three hundred eighty-three thousand, seven hundred forty-four".