397818517793 has 4 divisors (see below), whose sum is σ = 397820410260. Its totient is φ = 397816625328.

The previous prime is 397818517763. The next prime is 397818517799. The reversal of 397818517793 is 397715818793.

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 218545030144 + 179273487649 = 467488^2 + 423407^2 .

It is a cyclic number.

It is not a de Polignac number, because 397818517793 - 2³⁰ = 396744775969 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (397818517799) 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, 584930 + ... + 1066667.

It is an arithmetic number, because the mean of its divisors is an integer number (99455102565).

Almost surely, 2^397818517793 is an apocalyptic number.

It is an amenable number.

397818517793 is a deficient number, since it is larger than the sum of its proper divisors (1892467).

397818517793 is a wasteful number, since it uses less digits than its factorization.

397818517793 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1892466.

The product of its digits is 80015040, while the sum is 68.

The spelling of 397818517793 in words is "three hundred ninety-seven billion, eight hundred eighteen million, five hundred seventeen thousand, seven hundred ninety-three".