649012109 has 4 divisors (see below), whose sum is σ = 656831616. Its totient is φ = 641192604.

The previous prime is 649012093. The next prime is 649012139. The reversal of 649012109 is 901210946.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 649012109 - 2⁴ = 649012093 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 (649012139) 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, 3909629 + ... + 3909794.

It is an arithmetic number, because the mean of its divisors is an integer number (164207904).

Almost surely, 2^649012109 is an apocalyptic number.

It is an amenable number.

649012109 is a deficient number, since it is larger than the sum of its proper divisors (7819507).

649012109 is an equidigital number, since it uses as much as digits as its factorization.

649012109 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7819506.

The product of its (nonzero) digits is 3888, while the sum is 32.

The square root of 649012109 is about 25475.7160645192. The cubic root of 649012109 is about 865.8000367694.

The spelling of 649012109 in words is "six hundred forty-nine million, twelve thousand, one hundred nine".