648388717 has 4 divisors (see below), whose sum is σ = 648489600. Its totient is φ = 648287836.

The previous prime is 648388709. The next prime is 648388729. The reversal of 648388717 is 717883846.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 717883846 = 2 ⋅358941923.

It is a cyclic number.

It is not a de Polignac number, because 648388717 - 2³ = 648388709 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (648388217) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 40093 + ... + 53890.

It is an arithmetic number, because the mean of its divisors is an integer number (162122400).

Almost surely, 2^648388717 is an apocalyptic number.

It is an amenable number.

648388717 is a deficient number, since it is larger than the sum of its proper divisors (100883).

648388717 is an equidigital number, since it uses as much as digits as its factorization.

648388717 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 100882.

The product of its digits is 1806336, while the sum is 52.

The square root of 648388717 is about 25463.4781009979. The cubic root of 648388717 is about 865.5227405987.

The spelling of 648388717 in words is "six hundred forty-eight million, three hundred eighty-eight thousand, seven hundred seventeen".