645479565 has 16 divisors (see below), whose sum is σ = 1033344000. Its totient is φ = 344063552.

The previous prime is 645479563. The next prime is 645479573. The reversal of 645479565 is 565974546.

It is a cyclic number.

It is not a de Polignac number, because 645479565 - 2¹ = 645479563 is a prime.

It is a Smith number, since the sum of its digits (51) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645479561) 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, 18196 + ... + 40274.

It is an arithmetic number, because the mean of its divisors is an integer number (64584000).

Almost surely, 2^645479565 is an apocalyptic number.

It is an amenable number.

645479565 is a deficient number, since it is larger than the sum of its proper divisors (387864435).

645479565 is a wasteful number, since it uses less digits than its factorization.

645479565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24036.

The product of its digits is 4536000, while the sum is 51.

The square root of 645479565 is about 25406.2898708174. The cubic root of 645479565 is about 864.2263411099.

The spelling of 645479565 in words is "six hundred forty-five million, four hundred seventy-nine thousand, five hundred sixty-five".