645966573 has 16 divisors (see below), whose sum is σ = 984784896. Its totient is φ = 368953200.

The previous prime is 645966557. The next prime is 645966599. The reversal of 645966573 is 375669546.

It is a happy number.

It is not a de Polignac number, because 645966573 - 2⁴ = 645966557 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645966533) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 50148 + ... + 61698.

It is an arithmetic number, because the mean of its divisors is an integer number (61549056).

Almost surely, 2^645966573 is an apocalyptic number.

It is an amenable number.

645966573 is a deficient number, since it is larger than the sum of its proper divisors (338818323).

645966573 is a wasteful number, since it uses less digits than its factorization.

645966573 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14224.

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

The square root of 645966573 is about 25415.8724619085. The cubic root of 645966573 is about 864.4436365689.

The spelling of 645966573 in words is "six hundred forty-five million, nine hundred sixty-six thousand, five hundred seventy-three".