640020117773 has 4 divisors (see below), whose sum is σ = 641140994208. Its totient is φ = 638899241340.

The previous prime is 640020117739. The next prime is 640020117797. The reversal of 640020117773 is 377711020046.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-640020117773 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 (640020116773) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 560437361 + ... + 560438502.

It is an arithmetic number, because the mean of its divisors is an integer number (160285248552).

Almost surely, 2^640020117773 is an apocalyptic number.

It is an amenable number.

640020117773 is a deficient number, since it is larger than the sum of its proper divisors (1120876435).

640020117773 is a wasteful number, since it uses less digits than its factorization.

640020117773 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1120876434.

The product of its (nonzero) digits is 49392, while the sum is 38.

The spelling of 640020117773 in words is "six hundred forty billion, twenty million, one hundred seventeen thousand, seven hundred seventy-three".