648491 has 4 divisors (see below), whose sum is σ = 659184. Its totient is φ = 637800.

The previous prime is 648481. The next prime is 648509. The reversal of 648491 is 194846.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 194846 = 2 ⋅97423.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-648491 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (648481) 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, 5255 + ... + 5376.

It is an arithmetic number, because the mean of its divisors is an integer number (164796).

2⁶⁴⁸⁴⁹¹ is an apocalyptic number.

648491 is a gapful number since it is divisible by the number (61) formed by its first and last digit.

648491 is a deficient number, since it is larger than the sum of its proper divisors (10693).

648491 is a wasteful number, since it uses less digits than its factorization.

648491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10692.

The product of its digits is 6912, while the sum is 32.

The square root of 648491 is about 805.2893889777. The cubic root of 648491 is about 86.5568250134.

The spelling of 648491 in words is "six hundred forty-eight thousand, four hundred ninety-one".