640382796 has 72 divisors (see below), whose sum is σ = 1651104000. Its totient is φ = 209230560.

The previous prime is 640382773. The next prime is 640382833. The reversal of 640382796 is 697283046.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 508015 + ... + 509273.

It is an arithmetic number, because the mean of its divisors is an integer number (22932000).

Almost surely, 2^640382796 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 640382796, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (825552000).

640382796 is an abundant number, since it is smaller than the sum of its proper divisors (1010721204).

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

640382796 is a wasteful number, since it uses less digits than its factorization.

640382796 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1539 (or 1534 counting only the distinct ones).

The product of its (nonzero) digits is 435456, while the sum is 45.

The square root of 640382796 is about 25305.7858206379. The cubic root of 640382796 is about 861.9456561402.

The spelling of 640382796 in words is "six hundred forty million, three hundred eighty-two thousand, seven hundred ninety-six".