649808506 has 4 divisors (see below), whose sum is σ = 974712762. Its totient is φ = 324904252.

The previous prime is 649808503. The next prime is 649808513. The reversal of 649808506 is 605808946.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 604717281 + 45091225 = 24591^2 + 6715^2 .

It is not an unprimeable number, because it can be changed into a prime (649808501) 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 as a sum of consecutive naturals, namely, 162452125 + ... + 162452128.

Almost surely, 2^649808506 is an apocalyptic number.

649808506 is a deficient number, since it is larger than the sum of its proper divisors (324904256).

649808506 is a wasteful number, since it uses less digits than its factorization.

649808506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 324904255.

The product of its (nonzero) digits is 414720, while the sum is 46.

The square root of 649808506 is about 25491.3417850061. The cubic root of 649808506 is about 866.1540305288.

The spelling of 649808506 in words is "six hundred forty-nine million, eight hundred eight thousand, five hundred six".