645567369 has 4 divisors (see below), whose sum is σ = 860756496. Its totient is φ = 430378244.

The previous prime is 645567361. The next prime is 645567407. The reversal of 645567369 is 963765546.

It is a happy number.

645567369 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 645567369 - 2³ = 645567361 is a prime.

It is a super-2 number, since 2×645567369² = 833514455835164322, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (645567361) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 107594559 + ... + 107594564.

It is an arithmetic number, because the mean of its divisors is an integer number (215189124).

Almost surely, 2^645567369 is an apocalyptic number.

It is an amenable number.

645567369 is a deficient number, since it is larger than the sum of its proper divisors (215189127).

645567369 is a wasteful number, since it uses less digits than its factorization.

645567369 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 215189126.

The product of its digits is 4082400, while the sum is 51.

The square root of 645567369 is about 25408.0178093451. The cubic root of 645567369 is about 864.2655259750.

The spelling of 645567369 in words is "six hundred forty-five million, five hundred sixty-seven thousand, three hundred sixty-nine".