645820488713 has 4 divisors (see below), whose sum is σ = 645904076160. Its totient is φ = 645736901268.

The previous prime is 645820488707. The next prime is 645820488737. The reversal of 645820488713 is 317884028546.

645820488713 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 not a de Polignac number, because 645820488713 - 2⁴ = 645820488697 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (645820488743) 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, 41782133 + ... + 41797586.

It is an arithmetic number, because the mean of its divisors is an integer number (161476019040).

Almost surely, 2^645820488713 is an apocalyptic number.

It is an amenable number.

645820488713 is a deficient number, since it is larger than the sum of its proper divisors (83587447).

645820488713 is an equidigital number, since it uses as much as digits as its factorization.

645820488713 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83587446.

The product of its (nonzero) digits is 10321920, while the sum is 56.

The spelling of 645820488713 in words is "six hundred forty-five billion, eight hundred twenty million, four hundred eighty-eight thousand, seven hundred thirteen".