649757 has 8 divisors (see below), whose sum is σ = 707256. Its totient is φ = 594432.

The previous prime is 649751. The next prime is 649769. The reversal of 649757 is 757946.

It can be written as a sum of positive squares in 4 ways, for example, as 498436 + 151321 = 706^2 + 389^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 649757 - 2⁸ = 649501 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 649757.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 649757.

It is not an unprimeable number, because it can be changed into a prime (649751) 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 7 ways as a sum of consecutive naturals, for example, 113 + ... + 1145.

It is an arithmetic number, because the mean of its divisors is an integer number (88407).

2⁶⁴⁹⁷⁵⁷ is an apocalyptic number.

It is an amenable number.

649757 is a deficient number, since it is larger than the sum of its proper divisors (57499).

649757 is a wasteful number, since it uses less digits than its factorization.

649757 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1087.

The product of its digits is 52920, while the sum is 38.

The square root of 649757 is about 806.0750585398. The cubic root of 649757 is about 86.6131145167.

The spelling of 649757 in words is "six hundred forty-nine thousand, seven hundred fifty-seven".