640420014666 has 8 divisors (see below), whose sum is σ = 1280840029344. Its totient is φ = 213473338220.

The previous prime is 640420014643. The next prime is 640420014671. The reversal of 640420014666 is 666410024046.

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

640420014666 is an admirable number.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 53368334550 + ... + 53368334561.

It is an arithmetic number, because the mean of its divisors is an integer number (160105003668).

Almost surely, 2^640420014666 is an apocalyptic number.

640420014666 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

640420014666 is a wasteful number, since it uses less digits than its factorization.

640420014666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 106736669116.

The product of its (nonzero) digits is 165888, while the sum is 39.

The spelling of 640420014666 in words is "six hundred forty billion, four hundred twenty million, fourteen thousand, six hundred sixty-six".