645475144 has 16 divisors (see below), whose sum is σ = 1273964400. Its totient is φ = 305751312.

The previous prime is 645475139. The next prime is 645475189. The reversal of 645475144 is 441574546.

It is a junction number, because it is equal to n+sod(n) for n = 645475097 and 645475106.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2123122 + ... + 2123425.

It is an arithmetic number, because the mean of its divisors is an integer number (79622775).

Almost surely, 2^645475144 is an apocalyptic number.

It is an amenable number.

645475144 is a deficient number, since it is larger than the sum of its proper divisors (628489256).

645475144 is a wasteful number, since it uses less digits than its factorization.

645475144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4246572 (or 4246568 counting only the distinct ones).

The product of its digits is 268800, while the sum is 40.

The square root of 645475144 is about 25406.2028646549. The cubic root of 645475144 is about 864.2243680273.

The spelling of 645475144 in words is "six hundred forty-five million, four hundred seventy-five thousand, one hundred forty-four".