648649 has 2 divisors, whose sum is σ = 648650. Its totient is φ = 648648.

The previous prime is 648631. The next prime is 648653. The reversal of 648649 is 946846.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 640000 + 8649 = 800^2 + 93^2 .

It is a cyclic number.

It is not a de Polignac number, because 648649 - 2⁵ = 648617 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (648619) 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 as a sum of consecutive naturals, namely, 324324 + 324325.

It is an arithmetic number, because the mean of its divisors is an integer number (324325).

2⁶⁴⁸⁶⁴⁹ is an apocalyptic number.

It is an amenable number.

648649 is a deficient number, since it is larger than the sum of its proper divisors (1).

648649 is an equidigital number, since it uses as much as digits as its factorization.

648649 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 41472, while the sum is 37.

The square root of 648649 is about 805.3874843825. The cubic root of 648649 is about 86.5638540844.

It can be divided in two parts, 64 and 8649, that multiplied together give a square (553536 = 744²).

The spelling of 648649 in words is "six hundred forty-eight thousand, six hundred forty-nine".