645206073 has 16 divisors (see below), whose sum is σ = 872874240. Its totient is φ = 423876096.

The previous prime is 645206071. The next prime is 645206077. The reversal of 645206073 is 370602546.

It is not a de Polignac number, because 645206073 - 2¹ = 645206071 is a prime.

It is not an unprimeable number, because it can be changed into a prime (645206071) 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 15 ways as a sum of consecutive naturals, for example, 64911 + ... + 74187.

It is an arithmetic number, because the mean of its divisors is an integer number (54554640).

Almost surely, 2^645206073 is an apocalyptic number.

It is an amenable number.

645206073 is a deficient number, since it is larger than the sum of its proper divisors (227668167).

645206073 is a wasteful number, since it uses less digits than its factorization.

645206073 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9616.

The product of its (nonzero) digits is 30240, while the sum is 33.

The square root of 645206073 is about 25400.9069326274. The cubic root of 645206073 is about 864.1042652698.

The spelling of 645206073 in words is "six hundred forty-five million, two hundred six thousand, seventy-three".