645277909 has 8 divisors (see below), whose sum is σ = 662381280. Its totient is φ = 628269936.

The previous prime is 645277907. The next prime is 645277921. The reversal of 645277909 is 909772546.

645277909 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 645277909 - 2¹ = 645277907 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 (645277901) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10039 + ... + 37300.

It is an arithmetic number, because the mean of its divisors is an integer number (82797660).

Almost surely, 2^645277909 is an apocalyptic number.

It is an amenable number.

645277909 is a deficient number, since it is larger than the sum of its proper divisors (17103371).

645277909 is a wasteful number, since it uses less digits than its factorization.

645277909 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47699.

The product of its (nonzero) digits is 952560, while the sum is 49.

The square root of 645277909 is about 25402.3209372687. The cubic root of 645277909 is about 864.1363333139.

The spelling of 645277909 in words is "six hundred forty-five million, two hundred seventy-seven thousand, nine hundred nine".