645275569 has 8 divisors (see below), whose sum is σ = 648672192. Its totient is φ = 641886000.

The previous prime is 645275483. The next prime is 645275639. The reversal of 645275569 is 965572546.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 645275569 - 2¹¹ = 645273521 is a prime.

It is a super-2 number, since 2×645275569² = 832761119896547522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (645275269) 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 7 ways as a sum of consecutive naturals, for example, 326067 + ... + 328039.

It is an arithmetic number, because the mean of its divisors is an integer number (81084024).

Almost surely, 2^645275569 is an apocalyptic number.

It is an amenable number.

645275569 is a deficient number, since it is larger than the sum of its proper divisors (3396623).

645275569 is a wasteful number, since it uses less digits than its factorization.

645275569 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3527.

The product of its digits is 2268000, while the sum is 49.

The square root of 645275569 is about 25402.2748784435. The cubic root of 645275569 is about 864.1352887607.

The spelling of 645275569 in words is "six hundred forty-five million, two hundred seventy-five thousand, five hundred sixty-nine".