645002871624 has 48 divisors (see below), whose sum is σ = 1751153964300. Its totient is φ = 214475272704.

The previous prime is 645002871593. The next prime is 645002871641. The reversal of 645002871624 is 426178200546.

645002871624 is a `hidden beast` number, since 6 + 4 + 500 + 2 + 87 + 1 + 62 + 4 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 486112939524 + 158889932100 = 697218^2 + 398610^2 .

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 645002871624.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 10922109 + ... + 10981004.

Almost surely, 2^645002871624 is an apocalyptic number.

It is an amenable number.

645002871624 is an abundant number, since it is smaller than the sum of its proper divisors (1106151092676).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

645002871624 is a wasteful number, since it uses less digits than its factorization.

645002871624 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21903534 (or 21903527 counting only the distinct ones).

The product of its (nonzero) digits is 645120, while the sum is 45.

The spelling of 645002871624 in words is "six hundred forty-five billion, two million, eight hundred seventy-one thousand, six hundred twenty-four".