812378648517 has 4 divisors (see below), whose sum is σ = 1083171531360. Its totient is φ = 541585765676.

The previous prime is 812378648467. The next prime is 812378648531. The reversal of 812378648517 is 715846873218.

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.

It is a cyclic number.

It is not a de Polignac number, because 812378648517 - 2⁶ = 812378648453 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (812378647517) 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, 135396441417 + ... + 135396441422.

It is an arithmetic number, because the mean of its divisors is an integer number (270792882840).

Almost surely, 2^812378648517 is an apocalyptic number.

It is an amenable number.

812378648517 is a deficient number, since it is larger than the sum of its proper divisors (270792882843).

812378648517 is a wasteful number, since it uses less digits than its factorization.

812378648517 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 270792882842.

The product of its digits is 18063360, while the sum is 60.

The spelling of 812378648517 in words is "eight hundred twelve billion, three hundred seventy-eight million, six hundred forty-eight thousand, five hundred seventeen".