640168810 has 16 divisors (see below), whose sum is σ = 1153585152. Its totient is φ = 255782800.

The previous prime is 640168807. The next prime is 640168889. The reversal of 640168810 is 18861046.

640168810 is digitally balanced in base 6, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×640168810² = 819632210593632200, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 26026 + ... + 44245.

It is an arithmetic number, because the mean of its divisors is an integer number (72099072).

Almost surely, 2^640168810 is an apocalyptic number.

640168810 is a deficient number, since it is larger than the sum of its proper divisors (513416342).

640168810 is a wasteful number, since it uses less digits than its factorization.

640168810 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71189.

The product of its (nonzero) digits is 9216, while the sum is 34.

The square root of 640168810 is about 25301.5574619429. The cubic root of 640168810 is about 861.8496381270.

The spelling of 640168810 in words is "six hundred forty million, one hundred sixty-eight thousand, eight hundred ten".