645356045 has 4 divisors (see below), whose sum is σ = 774427260. Its totient is φ = 516284832.

The previous prime is 645356009. The next prime is 645356051. The reversal of 645356045 is 540653546.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 509540329 + 135815716 = 22573^2 + 11654^2 .

It is a cyclic number.

It is not a de Polignac number, because 645356045 - 2⁶ = 645355981 is a prime.

It is a congruent number.

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, 64535600 + ... + 64535609.

It is an arithmetic number, because the mean of its divisors is an integer number (193606815).

Almost surely, 2^645356045 is an apocalyptic number.

It is an amenable number.

645356045 is a deficient number, since it is larger than the sum of its proper divisors (129071215).

645356045 is a wasteful number, since it uses less digits than its factorization.

645356045 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 129071214.

The product of its (nonzero) digits is 216000, while the sum is 38.

The square root of 645356045 is about 25403.8588604172. The cubic root of 645356045 is about 864.1712110157.

The spelling of 645356045 in words is "six hundred forty-five million, three hundred fifty-six thousand, forty-five".