640718616613 has 8 divisors (see below), whose sum is σ = 678416316480. Its totient is φ = 603021846720.

The previous prime is 640718616599. The next prime is 640718616661. The reversal of 640718616613 is 316616817046.

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

It is a cyclic number.

It is not a de Polignac number, because 640718616613 - 2¹³ = 640718608421 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640718616673) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1597648 + ... + 1958038.

It is an arithmetic number, because the mean of its divisors is an integer number (84802039560).

Almost surely, 2^640718616613 is an apocalyptic number.

It is an amenable number.

640718616613 is a deficient number, since it is larger than the sum of its proper divisors (37697699867).

640718616613 is a wasteful number, since it uses less digits than its factorization.

640718616613 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 464987.

The product of its (nonzero) digits is 870912, while the sum is 49.

The spelling of 640718616613 in words is "six hundred forty billion, seven hundred eighteen million, six hundred sixteen thousand, six hundred thirteen".