649903 has 4 divisors (see below), whose sum is σ = 653400. Its totient is φ = 646408.

The previous prime is 649897. The next prime is 649907. The reversal of 649903 is 309946.

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

It is a cyclic number.

It is not a de Polignac number, because 649903 - 2⁵ = 649871 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (649907) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1453 + ... + 1846.

It is an arithmetic number, because the mean of its divisors is an integer number (163350).

2⁶⁴⁹⁹⁰³ is an apocalyptic number.

649903 is a deficient number, since it is larger than the sum of its proper divisors (3497).

649903 is a wasteful number, since it uses less digits than its factorization.

649903 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3496.

The product of its (nonzero) digits is 5832, while the sum is 31.

The square root of 649903 is about 806.1656157391. The cubic root of 649903 is about 86.6196013355.

The spelling of 649903 in words is "six hundred forty-nine thousand, nine hundred three".