649863 has 20 divisors (see below), whose sum is σ = 993168. Its totient is φ = 423360.

The previous prime is 649849. The next prime is 649867. The reversal of 649863 is 368946.

649863 is a `hidden beast` number, since 649 + 8 + 6 + 3 = 666.

It is not a de Polignac number, because 649863 - 2⁶ = 649799 is a prime.

It is a nialpdrome in base 15.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (649867) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 5695 + ... + 5807.

2⁶⁴⁹⁸⁶³ is an apocalyptic number.

649863 is a deficient number, since it is larger than the sum of its proper divisors (343305).

649863 is a wasteful number, since it uses less digits than its factorization.

649863 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 196 (or 187 counting only the distinct ones).

The product of its digits is 31104, while the sum is 36.

The square root of 649863 is about 806.1408065593. The cubic root of 649863 is about 86.6178242215.

It can be divided in two parts, 6498 and 63, that added together give a 8-th power (6561 = 3⁸).

The spelling of 649863 in words is "six hundred forty-nine thousand, eight hundred sixty-three".