640278912 has 256 divisors, whose sum is σ = 2130347520. Its totient is φ = 165888000.

The previous prime is 640278889. The next prime is 640278941. The reversal of 640278912 is 219872046.

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2550787 + ... + 2551037.

It is an arithmetic number, because the mean of its divisors is an integer number (8321670).

Almost surely, 2^640278912 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 640278912, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1065173760).

640278912 is an abundant number, since it is smaller than the sum of its proper divisors (1490068608).

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

640278912 is a wasteful number, since it uses less digits than its factorization.

640278912 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 361 (or 349 counting only the distinct ones).

The product of its (nonzero) digits is 48384, while the sum is 39.

The square root of 640278912 is about 25303.7331633101. The cubic root of 640278912 is about 861.8990448500.

The spelling of 640278912 in words is "six hundred forty million, two hundred seventy-eight thousand, nine hundred twelve".