645322440013 has 2 divisors, whose sum is σ = 645322440014. Its totient is φ = 645322440012.

The previous prime is 645322440011. The next prime is 645322440053. The reversal of 645322440013 is 310044223546.

645322440013 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 610489070244 + 34833369769 = 781338^2 + 186637^2 .

It is a cyclic number.

It is not a de Polignac number, because 645322440013 - 2¹ = 645322440011 is a prime.

Together with 645322440011, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (645322440011) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322661220006 + 322661220007.

It is an arithmetic number, because the mean of its divisors is an integer number (322661220007).

Almost surely, 2^645322440013 is an apocalyptic number.

It is an amenable number.

645322440013 is a deficient number, since it is larger than the sum of its proper divisors (1).

645322440013 is an equidigital number, since it uses as much as digits as its factorization.

645322440013 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 69120, while the sum is 34.

Adding to 645322440013 its reverse (310044223546), we get a palindrome (955366663559).

The spelling of 645322440013 in words is "six hundred forty-five billion, three hundred twenty-two million, four hundred forty thousand, thirteen".