645145133 has 4 divisors (see below), whose sum is σ = 679100160. Its totient is φ = 611190108.

The previous prime is 645145129. The next prime is 645145213. The reversal of 645145133 is 331541546.

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 645145133 - 2² = 645145129 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 645145133.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645142133) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16977485 + ... + 16977522.

It is an arithmetic number, because the mean of its divisors is an integer number (169775040).

Almost surely, 2^645145133 is an apocalyptic number.

It is an amenable number.

645145133 is a deficient number, since it is larger than the sum of its proper divisors (33955027).

645145133 is a wasteful number, since it uses less digits than its factorization.

645145133 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33955026.

The product of its digits is 21600, while the sum is 32.

The square root of 645145133 is about 25399.7073408337. The cubic root of 645145133 is about 864.0770594028.

Adding to 645145133 its reverse (331541546), we get a palindrome (976686679).

The spelling of 645145133 in words is "six hundred forty-five million, one hundred forty-five thousand, one hundred thirty-three".