181665326545 has 8 divisors (see below), whose sum is σ = 225515577960. Its totient is φ = 140320803840.

The previous prime is 181665326539. The next prime is 181665326599. The reversal of 181665326545 is 545623566181.

It can be written as a sum of positive squares in 4 ways, for example, as 41267484736 + 140397841809 = 203144^2 + 374697^2 .

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

It is not a de Polignac number, because 181665326545 - 2³ = 181665326537 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 181665326492 and 181665326501.

It is an unprimeable number.

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 in 7 ways as a sum of consecutive naturals, for example, 626432016 + ... + 626432305.

It is an arithmetic number, because the mean of its divisors is an integer number (28189447245).

Almost surely, 2^181665326545 is an apocalyptic number.

It is an amenable number.

181665326545 is a deficient number, since it is larger than the sum of its proper divisors (43850251415).

181665326545 is a wasteful number, since it uses less digits than its factorization.

181665326545 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1252864355.

The product of its digits is 5184000, while the sum is 52.

The spelling of 181665326545 in words is "one hundred eighty-one billion, six hundred sixty-five million, three hundred twenty-six thousand, five hundred forty-five".