645188840813 has 16 divisors (see below), whose sum is σ = 734509541376. Its totient is φ = 560983872240.

The previous prime is 645188840753. The next prime is 645188840927. The reversal of 645188840813 is 318048881546.

It is not a de Polignac number, because 645188840813 - 2¹⁶ = 645188775277 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645188890813) 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, 2893856 + ... + 3108822.

It is an arithmetic number, because the mean of its divisors is an integer number (45906846336).

Almost surely, 2^645188840813 is an apocalyptic number.

It is an amenable number.

645188840813 is a deficient number, since it is larger than the sum of its proper divisors (89320700563).

645188840813 is a wasteful number, since it uses less digits than its factorization.

645188840813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 226864.

The product of its (nonzero) digits is 5898240, while the sum is 56.

The spelling of 645188840813 in words is "six hundred forty-five billion, one hundred eighty-eight million, eight hundred forty thousand, eight hundred thirteen".