1816873133 has 4 divisors (see below), whose sum is σ = 1818536508. Its totient is φ = 1815209760.

The previous prime is 1816873117. The next prime is 1816873151. The reversal of 1816873133 is 3313786181.

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 1479710089 + 337163044 = 38467^2 + 18362^2 .

It is a cyclic number.

It is not a de Polignac number, because 1816873133 - 2⁴ = 1816873117 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1816873153) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 830048 + ... + 832233.

It is an arithmetic number, because the mean of its divisors is an integer number (454634127).

Almost surely, 2^1816873133 is an apocalyptic number.

It is an amenable number.

1816873133 is a deficient number, since it is larger than the sum of its proper divisors (1663375).

1816873133 is a wasteful number, since it uses less digits than its factorization.

1816873133 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1663374.

The product of its digits is 72576, while the sum is 41.

The square root of 1816873133 is about 42624.7948147554. The cubic root of 1816873133 is about 1220.2295395835.

The spelling of 1816873133 in words is "one billion, eight hundred sixteen million, eight hundred seventy-three thousand, one hundred thirty-three".