645512732 has 12 divisors (see below), whose sum is σ = 1155918456. Its totient is φ = 315250320.

The previous prime is 645512731. The next prime is 645512741. The reversal of 645512732 is 237215546.

It is a junction number, because it is equal to n+sod(n) for n = 645512692 and 645512701.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645512731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1876319 + ... + 1876662.

It is an arithmetic number, because the mean of its divisors is an integer number (96326538).

Almost surely, 2^645512732 is an apocalyptic number.

It is an amenable number.

645512732 is a deficient number, since it is larger than the sum of its proper divisors (510405724).

645512732 is a wasteful number, since it uses less digits than its factorization.

645512732 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3753028 (or 3753026 counting only the distinct ones).

The product of its digits is 50400, while the sum is 35.

The square root of 645512732 is about 25406.9425944957. The cubic root of 645512732 is about 864.2411431814.

The spelling of 645512732 in words is "six hundred forty-five million, five hundred twelve thousand, seven hundred thirty-two".