645053364021 has 64 divisors (see below), whose sum is σ = 977921003520. Its totient is φ = 374624490240.

The previous prime is 645053363953. The next prime is 645053364037. The reversal of 645053364021 is 120463350546.

It is not a de Polignac number, because 645053364021 - 2⁹ = 645053363509 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645053364721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 168727716 + ... + 168731538.

It is an arithmetic number, because the mean of its divisors is an integer number (15280015680).

Almost surely, 2^645053364021 is an apocalyptic number.

It is an amenable number.

645053364021 is a deficient number, since it is larger than the sum of its proper divisors (332867639499).

645053364021 is a wasteful number, since it uses less digits than its factorization.

645053364021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5146.

The product of its (nonzero) digits is 259200, while the sum is 39.

The spelling of 645053364021 in words is "six hundred forty-five billion, fifty-three million, three hundred sixty-four thousand, twenty-one".