640640020013 has 8 divisors (see below), whose sum is σ = 732870176640. Its totient is φ = 548587401840.

The previous prime is 640640020001. The next prime is 640640020157. The reversal of 640640020013 is 310020046046.

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 640640020013 - 2³⁴ = 623460150829 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640640020313) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 44376878 + ... + 44391311.

It is an arithmetic number, because the mean of its divisors is an integer number (91608772080).

Almost surely, 2^640640020013 is an apocalyptic number.

It is an amenable number.

640640020013 is a deficient number, since it is larger than the sum of its proper divisors (92230156627).

640640020013 is a wasteful number, since it uses less digits than its factorization.

640640020013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 88769227.

The product of its (nonzero) digits is 3456, while the sum is 26.

Adding to 640640020013 its reverse (310020046046), we get a palindrome (950660066059).

The spelling of 640640020013 in words is "six hundred forty billion, six hundred forty million, twenty thousand, thirteen".