645443212 has 12 divisors (see below), whose sum is σ = 1135837080. Its totient is φ = 320918336.

The previous prime is 645443209. The next prime is 645443213. The reversal of 645443212 is 212344546.

645443212 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not an unprimeable number, because it can be changed into a prime (645443213) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 450013 + ... + 451444.

It is an arithmetic number, because the mean of its divisors is an integer number (94653090).

Almost surely, 2^645443212 is an apocalyptic number.

It is an amenable number.

645443212 is a deficient number, since it is larger than the sum of its proper divisors (490393868).

645443212 is a wasteful number, since it uses less digits than its factorization.

645443212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 901640 (or 901638 counting only the distinct ones).

The product of its digits is 23040, while the sum is 31.

The square root of 645443212 is about 25405.5744276724. The cubic root of 645443212 is about 864.2101165787.

Adding to 645443212 its reverse (212344546), we get a palindrome (857787758).

The spelling of 645443212 in words is "six hundred forty-five million, four hundred forty-three thousand, two hundred twelve".