645873202378547 has 16 divisors (see below), whose sum is σ = 758788846297440. Its totient is φ = 541990963929600.

The previous prime is 645873202378507. The next prime is 645873202378549. The reversal of 645873202378547 is 745873202378546.

645873202378547 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 645873202378547 - 2⁶ = 645873202378483 is a prime.

It is a Smith number, since the sum of its digits (71) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (645873202378549) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 221717147 + ... + 224611307.

It is an arithmetic number, because the mean of its divisors is an integer number (47424302893590).

Almost surely, 2^{645873202378547} is an apocalyptic number.

645873202378547 is a deficient number, since it is larger than the sum of its proper divisors (112915643918893).

645873202378547 is a wasteful number, since it uses less digits than its factorization.

645873202378547 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4454774.

The product of its (nonzero) digits is 1896652800, while the sum is 71.

Subtracting 645873202378547 from its reverse (745873202378546), we obtain a palindrome (99999999999999).

The spelling of 645873202378547 in words is "six hundred forty-five trillion, eight hundred seventy-three billion, two hundred two million, three hundred seventy-eight thousand, five hundred forty-seven".