1809909529345 has 4 divisors (see below), whose sum is σ = 2171891435220. Its totient is φ = 1447927623472.

The previous prime is 1809909529247. The next prime is 1809909529381. The reversal of 1809909529345 is 5439259099081.

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

It can be written as a sum of positive squares in 2 ways, for example, as 1062777489921 + 747132039424 = 1030911^2 + 864368^2 .

It is a cyclic number.

It is not a de Polignac number, because 1809909529345 - 2¹⁷ = 1809909398273 is a prime.

It is a super-2 number, since 2×1809909529345² (a number of 25 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 180990952930 + ... + 180990952939.

It is an arithmetic number, because the mean of its divisors is an integer number (542972858805).

Almost surely, 2^{1809909529345} is an apocalyptic number.

It is an amenable number.

1809909529345 is a deficient number, since it is larger than the sum of its proper divisors (361981905875).

1809909529345 is an equidigital number, since it uses as much as digits as its factorization.

1809909529345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 361981905874.

The product of its (nonzero) digits is 31492800, while the sum is 64.

The spelling of 1809909529345 in words is "one trillion, eight hundred nine billion, nine hundred nine million, five hundred twenty-nine thousand, three hundred forty-five".