648979 has 4 divisors (see below), whose sum is σ = 659680. Its totient is φ = 638280.

The previous prime is 648971. The next prime is 648997. The reversal of 648979 is 979846.

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 648979 - 2³ = 648971 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (648971) 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 3 ways as a sum of consecutive naturals, for example, 5259 + ... + 5380.

It is an arithmetic number, because the mean of its divisors is an integer number (164920).

2⁶⁴⁸⁹⁷⁹ is an apocalyptic number.

648979 is a deficient number, since it is larger than the sum of its proper divisors (10701).

648979 is a wasteful number, since it uses less digits than its factorization.

648979 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10700.

The product of its digits is 108864, while the sum is 43.

The square root of 648979 is about 805.5923286626. The cubic root of 648979 is about 86.5785313746.

The spelling of 648979 in words is "six hundred forty-eight thousand, nine hundred seventy-nine".