1809534073 has 4 divisors (see below), whose sum is σ = 1839198628. Its totient is φ = 1779869520.

The previous prime is 1809534029. The next prime is 1809534119. The reversal of 1809534073 is 3704359081.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3704359081 = 37 ⋅100117813.

It can be written as a sum of positive squares in 2 ways, for example, as 441126009 + 1368408064 = 21003^2 + 36992^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1809534073 is a prime.

It is a super-2 number, since 2×1809534073² = 6548827122695938658, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1809534473) by changing a digit.

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, 14832186 + ... + 14832307.

It is an arithmetic number, because the mean of its divisors is an integer number (459799657).

Almost surely, 2^1809534073 is an apocalyptic number.

It is an amenable number.

1809534073 is a deficient number, since it is larger than the sum of its proper divisors (29664555).

1809534073 is an equidigital number, since it uses as much as digits as its factorization.

1809534073 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29664554.

The product of its (nonzero) digits is 90720, while the sum is 40.

The square root of 1809534073 is about 42538.6186070963. The cubic root of 1809534073 is about 1218.5843278532.

The spelling of 1809534073 in words is "one billion, eight hundred nine million, five hundred thirty-four thousand, seventy-three".