640301643 has 48 divisors (see below), whose sum is σ = 982238400. Its totient is φ = 401345280.

The previous prime is 640301603. The next prime is 640301671. The reversal of 640301643 is 346103046.

640301643 is a `hidden beast` number, since 640 + 3 + 0 + 16 + 4 + 3 = 666.

It is not a de Polignac number, because 640301643 - 2⁶ = 640301579 is a prime.

It is not an unprimeable number, because it can be changed into a prime (640301603) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2019721 + ... + 2020037.

It is an arithmetic number, because the mean of its divisors is an integer number (20463300).

Almost surely, 2^640301643 is an apocalyptic number.

640301643 is a deficient number, since it is larger than the sum of its proper divisors (341936757).

640301643 is a wasteful number, since it uses less digits than its factorization.

640301643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 532 (or 529 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 27.

The square root of 640301643 is about 25304.1823222961. The cubic root of 640301643 is about 861.9092443610.

Adding to 640301643 its reverse (346103046), we get a palindrome (986404689).

The spelling of 640301643 in words is "six hundred forty million, three hundred one thousand, six hundred forty-three".