640394010 has 48 divisors (see below), whose sum is σ = 1668971304. Its totient is φ = 170366976.

The previous prime is 640394003. The next prime is 640394011. The reversal of 640394010 is 10493046.

640394010 is a `hidden beast` number, since 640 + 3 + 9 + 4 + 0 + 10 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 566106849 + 74287161 = 23793^2 + 8619^2 .

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (640394011) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 30754 + ... + 47186.

Almost surely, 2^640394010 is an apocalyptic number.

640394010 is an abundant number, since it is smaller than the sum of its proper divisors (1028577294).

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

640394010 is a wasteful number, since it uses less digits than its factorization.

640394010 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16879 (or 16876 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 27.

The square root of 640394010 is about 25306.0073895508. The cubic root of 640394010 is about 861.9506874028.

The spelling of 640394010 in words is "six hundred forty million, three hundred ninety-four thousand, ten".