640336020 has 24 divisors (see below), whose sum is σ = 1792941024. Its totient is φ = 170756256.

The previous prime is 640336013. The next prime is 640336033. The reversal of 640336020 is 20633046.

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 7 ways as a sum of consecutive naturals, for example, 5336074 + ... + 5336193.

It is an arithmetic number, because the mean of its divisors is an integer number (74705876).

Almost surely, 2^640336020 is an apocalyptic number.

640336020 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

640336020 is an abundant number, since it is smaller than the sum of its proper divisors (1152605004).

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

640336020 is a wasteful number, since it uses less digits than its factorization.

640336020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10672279 (or 10672277 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 24.

The square root of 640336020 is about 25304.8615882403. The cubic root of 640336020 is about 861.9246690306.

Adding to 640336020 its reverse (20633046), we get a palindrome (660969066).

The spelling of 640336020 in words is "six hundred forty million, three hundred thirty-six thousand, twenty".