640204460806 has 8 divisors (see below), whose sum is σ = 962598593880. Its totient is φ = 319338262848.

The previous prime is 640204460789. The next prime is 640204460813. The reversal of 640204460806 is 608064402046.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-3 number, since 3×640204460806³ (a number of 36 digits) contains 333 as substring.

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 3 ways as a sum of consecutive naturals, for example, 381982731 + ... + 381984406.

It is an arithmetic number, because the mean of its divisors is an integer number (120324824235).

Almost surely, 2^640204460806 is an apocalyptic number.

640204460806 is a deficient number, since it is larger than the sum of its proper divisors (322394133074).

640204460806 is a wasteful number, since it uses less digits than its factorization.

640204460806 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 763967558.

The product of its (nonzero) digits is 221184, while the sum is 40.

The spelling of 640204460806 in words is "six hundred forty billion, two hundred four million, four hundred sixty thousand, eight hundred six".