640256134166 has 16 divisors (see below), whose sum is σ = 1048321916928. Its totient is φ = 290850498600.

The previous prime is 640256134159. The next prime is 640256134171. The reversal of 640256134166 is 661431652046.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8713430 + ... + 8786601.

It is an arithmetic number, because the mean of its divisors is an integer number (65520119808).

Almost surely, 2^640256134166 is an apocalyptic number.

640256134166 is a deficient number, since it is larger than the sum of its proper divisors (408065782762).

640256134166 is a wasteful number, since it uses less digits than its factorization.

640256134166 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17501707.

The product of its (nonzero) digits is 622080, while the sum is 44.

The spelling of 640256134166 in words is "six hundred forty billion, two hundred fifty-six million, one hundred thirty-four thousand, one hundred sixty-six".