648557071 has 4 divisors (see below), whose sum is σ = 648875032. Its totient is φ = 648239112.

The previous prime is 648557069. The next prime is 648557081. The reversal of 648557071 is 170755846.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 170755846 = 2 ⋅85377923.

It is a cyclic number.

It is not a de Polignac number, because 648557071 - 2¹ = 648557069 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 (648557051) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 155901 + ... + 160006.

It is an arithmetic number, because the mean of its divisors is an integer number (162218758).

Almost surely, 2^648557071 is an apocalyptic number.

648557071 is a deficient number, since it is larger than the sum of its proper divisors (317961).

648557071 is a wasteful number, since it uses less digits than its factorization.

648557071 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 317960.

The product of its (nonzero) digits is 235200, while the sum is 43.

The square root of 648557071 is about 25466.7836799231. The cubic root of 648557071 is about 865.5976450513.

The spelling of 648557071 in words is "six hundred forty-eight million, five hundred fifty-seven thousand, seventy-one".