511731668641 has 4 divisors (see below), whose sum is σ = 511741238932. Its totient is φ = 511722098352.

The previous prime is 511731668599. The next prime is 511731668647. The reversal of 511731668641 is 146866137115.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 146866137115 = 5 ⋅29373227423.

It can be written as a sum of positive squares in 2 ways, for example, as 316880052241 + 194851616400 = 562921^2 + 441420^2 .

It is a cyclic number.

It is not a de Polignac number, because 511731668641 - 2¹³ = 511731660449 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (511731668647) 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, 4704486 + ... + 4812031.

It is an arithmetic number, because the mean of its divisors is an integer number (127935309733).

Almost surely, 2^511731668641 is an apocalyptic number.

It is an amenable number.

511731668641 is a deficient number, since it is larger than the sum of its proper divisors (9570291).

511731668641 is an equidigital number, since it uses as much as digits as its factorization.

511731668641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9570290.

The product of its digits is 725760, while the sum is 49.

The spelling of 511731668641 in words is "five hundred eleven billion, seven hundred thirty-one million, six hundred sixty-eight thousand, six hundred forty-one".