649689 has 8 divisors (see below), whose sum is σ = 917280. Its totient is φ = 407616.

The previous prime is 649661. The next prime is 649697. The reversal of 649689 is 986946.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 649689 - 2⁵ = 649657 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 649689.

It is not an unprimeable number, because it can be changed into a prime (649619) 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, 6319 + ... + 6420.

It is an arithmetic number, because the mean of its divisors is an integer number (114660).

2⁶⁴⁹⁶⁸⁹ is an apocalyptic number.

It is an amenable number.

649689 is a deficient number, since it is larger than the sum of its proper divisors (267591).

649689 is a wasteful number, since it uses less digits than its factorization.

649689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12759.

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

The square root of 649689 is about 806.0328777413. The cubic root of 649689 is about 86.6100929270.

The spelling of 649689 in words is "six hundred forty-nine thousand, six hundred eighty-nine".