1798805609 has 4 divisors (see below), whose sum is σ = 1801612500. Its totient is φ = 1795998720.

The previous prime is 1798805599. The next prime is 1798805623. The reversal of 1798805609 is 9065088971.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9065088971 = 41 ⋅221099731.

It can be written as a sum of positive squares in 2 ways, for example, as 1687566400 + 111239209 = 41080^2 + 10547^2 .

It is a cyclic number.

It is not a de Polignac number, because 1798805609 - 2¹² = 1798801513 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1798805909) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1402484 + ... + 1403765.

It is an arithmetic number, because the mean of its divisors is an integer number (450403125).

Almost surely, 2^1798805609 is an apocalyptic number.

It is an amenable number.

1798805609 is a deficient number, since it is larger than the sum of its proper divisors (2806891).

1798805609 is an equidigital number, since it uses as much as digits as its factorization.

1798805609 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2806890.

The product of its (nonzero) digits is 1088640, while the sum is 53.

The square root of 1798805609 is about 42412.3285024532. The cubic root of 1798805609 is about 1216.1712830143.

The spelling of 1798805609 in words is "one billion, seven hundred ninety-eight million, eight hundred five thousand, six hundred nine".