131817820671805 has 8 divisors (see below), whose sum is σ = 158182140857400. Its totient is φ = 105453752503296.

The previous prime is 131817820671791. The next prime is 131817820671833. The reversal of 131817820671805 is 508176028718131.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 14174577427396 + 117643243244409 = 3764914^2 + 10846347^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 131817820671805 - 2⁵ = 131817820671773 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 131817820671805.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 61851640 + ... + 63947329.

It is an arithmetic number, because the mean of its divisors is an integer number (19772767607175).

Almost surely, 2^{131817820671805} is an apocalyptic number.

It is an amenable number.

131817820671805 is a deficient number, since it is larger than the sum of its proper divisors (26364320185595).

131817820671805 is a wasteful number, since it uses less digits than its factorization.

131817820671805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 126008543.

The product of its (nonzero) digits is 4515840, while the sum is 58.

The spelling of 131817820671805 in words is "one hundred thirty-one trillion, eight hundred seventeen billion, eight hundred twenty million, six hundred seventy-one thousand, eight hundred five".