1812223817 has 4 divisors (see below), whose sum is σ = 1918825236. Its totient is φ = 1705622400.

The previous prime is 1812223813. The next prime is 1812223867. The reversal of 1812223817 is 7183222181.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7183222181 = 41 ⋅175200541.

It can be written as a sum of positive squares in 2 ways, for example, as 984453376 + 827770441 = 31376^2 + 28771^2 .

It is a cyclic number.

It is not a de Polignac number, because 1812223817 - 2² = 1812223813 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1812223811) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 53300684 + ... + 53300717.

It is an arithmetic number, because the mean of its divisors is an integer number (479706309).

Almost surely, 2^1812223817 is an apocalyptic number.

1812223817 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

It is an amenable number.

1812223817 is a deficient number, since it is larger than the sum of its proper divisors (106601419).

1812223817 is a wasteful number, since it uses less digits than its factorization.

1812223817 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 106601418.

The product of its digits is 10752, while the sum is 35.

The square root of 1812223817 is about 42570.2221864063. Note that the first 3 decimals coincide. The cubic root of 1812223817 is about 1219.1878086534.

Adding to 1812223817 its reverse (7183222181), we get a palindrome (8995445998).

The spelling of 1812223817 in words is "one billion, eight hundred twelve million, two hundred twenty-three thousand, eight hundred seventeen".