1812805505 has 8 divisors (see below), whose sum is σ = 2486133312. Its totient is φ = 1243066608.

The previous prime is 1812805483. The next prime is 1812805517. The reversal of 1812805505 is 5055082181.

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

It is not a de Polignac number, because 1812805505 - 2⁸ = 1812805249 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (35), and also a Moran number because the ratio is a prime number: 51794443 = 1812805505 / (1 + 8 + 1 + 2 + 8 + 0 + 5 + 5 + 0 + 5).

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25897187 + ... + 25897256.

It is an arithmetic number, because the mean of its divisors is an integer number (310766664).

Almost surely, 2^1812805505 is an apocalyptic number.

It is an amenable number.

1812805505 is a deficient number, since it is larger than the sum of its proper divisors (673327807).

1812805505 is an equidigital number, since it uses as much as digits as its factorization.

1812805505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51794455.

The product of its (nonzero) digits is 16000, while the sum is 35.

The square root of 1812805505 is about 42577.0537378997. The cubic root of 1812805505 is about 1219.3182397563.

Adding to 1812805505 its reverse (5055082181), we get a palindrome (6867887686).

The spelling of 1812805505 in words is "one billion, eight hundred twelve million, eight hundred five thousand, five hundred five".