645537303 has 24 divisors (see below), whose sum is σ = 990501200. Its totient is φ = 415503648.

The previous prime is 645537281. The next prime is 645537337. The reversal of 645537303 is 303735546.

645537303 is a `hidden beast` number, since 645 + 5 + 3 + 7 + 3 + 0 + 3 = 666.

It is not a de Polignac number, because 645537303 - 2⁸ = 645537047 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645537383) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 8493 + ... + 36921.

Almost surely, 2^645537303 is an apocalyptic number.

645537303 is a deficient number, since it is larger than the sum of its proper divisors (344963897).

645537303 is a wasteful number, since it uses less digits than its factorization.

645537303 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28496 (or 28461 counting only the distinct ones).

The product of its (nonzero) digits is 113400, while the sum is 36.

The square root of 645537303 is about 25407.4261388280. The cubic root of 645537303 is about 864.2521086247.

The spelling of 645537303 in words is "six hundred forty-five million, five hundred thirty-seven thousand, three hundred three".