645275443 has 12 divisors (see below), whose sum is σ = 690902272. Its totient is φ = 602501760.

The previous prime is 645275437. The next prime is 645275461. The reversal of 645275443 is 344572546.

It is a de Polignac number, because none of the positive numbers 2^k-645275443 is a prime.

It is a hoax number, since the sum of its digits (40) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 645275396 and 645275405.

It is not an unprimeable number, because it can be changed into a prime (645275413) by changing a digit.

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, 27913 + ... + 45493.

Almost surely, 2^645275443 is an apocalyptic number.

645275443 is a deficient number, since it is larger than the sum of its proper divisors (45626829).

645275443 is a wasteful number, since it uses less digits than its factorization.

645275443 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17742 (or 17725 counting only the distinct ones).

The product of its digits is 403200, while the sum is 40.

The square root of 645275443 is about 25402.2723983505. The cubic root of 645275443 is about 864.1352325154.

The spelling of 645275443 in words is "six hundred forty-five million, two hundred seventy-five thousand, four hundred forty-three".