671505231823 has 4 divisors (see below), whose sum is σ = 672378451360. Its totient is φ = 670632012288.

The previous prime is 671505231811. The next prime is 671505231841. The reversal of 671505231823 is 328132505176.

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

It is a cyclic number.

It is not a de Polignac number, because 671505231823 - 2⁵ = 671505231791 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 671505231823.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (671505231893) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 436608615 + ... + 436610152.

It is an arithmetic number, because the mean of its divisors is an integer number (168094612840).

Almost surely, 2^671505231823 is an apocalyptic number.

671505231823 is a deficient number, since it is larger than the sum of its proper divisors (873219537).

671505231823 is an equidigital number, since it uses as much as digits as its factorization.

671505231823 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 873219536.

The product of its (nonzero) digits is 302400, while the sum is 43.

Adding to 671505231823 its reverse (328132505176), we get a palindrome (999637736999).

The spelling of 671505231823 in words is "six hundred seventy-one billion, five hundred five million, two hundred thirty-one thousand, eight hundred twenty-three".