648802810813 has 4 divisors (see below), whose sum is σ = 648822558780. Its totient is φ = 648783062848.

The previous prime is 648802810741. The next prime is 648802810829. The reversal of 648802810813 is 318018208846.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 539280203449 + 109522607364 = 734357^2 + 330942^2 .

It is a cyclic number.

It is not a de Polignac number, because 648802810813 - 2¹³ = 648802802621 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 (648802810853) 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, 9824620 + ... + 9890437.

It is an arithmetic number, because the mean of its divisors is an integer number (162205639695).

Almost surely, 2^648802810813 is an apocalyptic number.

It is an amenable number.

648802810813 is a deficient number, since it is larger than the sum of its proper divisors (19747967).

648802810813 is a wasteful number, since it uses less digits than its factorization.

648802810813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19747966.

The product of its (nonzero) digits is 589824, while the sum is 49.

The spelling of 648802810813 in words is "six hundred forty-eight billion, eight hundred two million, eight hundred ten thousand, eight hundred thirteen".