671511818564 has 6 divisors (see below), whose sum is σ = 1175145682494. Its totient is φ = 335755909280.

The previous prime is 671511818563. The next prime is 671511818597. The reversal of 671511818564 is 465818115176.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 599370156100 + 72141662464 = 774190^2 + 268592^2 .

It is a super-2 number, since 2×671511818564² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (671511818563) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83938977317 + ... + 83938977324.

It is an arithmetic number, because the mean of its divisors is an integer number (195857613749).

Almost surely, 2^671511818564 is an apocalyptic number.

It is an amenable number.

671511818564 is a deficient number, since it is larger than the sum of its proper divisors (503633863930).

671511818564 is a wasteful number, since it uses less digits than its factorization.

671511818564 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 167877954645 (or 167877954643 counting only the distinct ones).

The product of its digits is 1612800, while the sum is 53.

The spelling of 671511818564 in words is "six hundred seventy-one billion, five hundred eleven million, eight hundred eighteen thousand, five hundred sixty-four".