649381209 has 8 divisors (see below), whose sum is σ = 877702752. Its totient is φ = 426990240.

The previous prime is 649381171. The next prime is 649381261. The reversal of 649381209 is 902183946.

649381209 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 not a de Polignac number, because 649381209 - 2²⁵ = 615826777 is a prime.

It is not an unprimeable number, because it can be changed into a prime (649381289) 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, 1482387 + ... + 1482824.

It is an arithmetic number, because the mean of its divisors is an integer number (109712844).

Almost surely, 2^649381209 is an apocalyptic number.

It is an amenable number.

649381209 is a deficient number, since it is larger than the sum of its proper divisors (228321543).

649381209 is a wasteful number, since it uses less digits than its factorization.

649381209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2965287.

The product of its (nonzero) digits is 93312, while the sum is 42.

The square root of 649381209 is about 25482.9591884459. The cubic root of 649381209 is about 865.9641355219.

The spelling of 649381209 in words is "six hundred forty-nine million, three hundred eighty-one thousand, two hundred nine".