1823840209 has 2 divisors, whose sum is σ = 1823840210. Its totient is φ = 1823840208.

The previous prime is 1823840197. The next prime is 1823840231. The reversal of 1823840209 is 9020483281.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1326416400 + 497423809 = 36420^2 + 22303^2 .

It is a cyclic number.

It is not a de Polignac number, because 1823840209 - 2²³ = 1815451601 is a prime.

It is not a weakly prime, because it can be changed into another prime (1823846209) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 911920104 + 911920105.

It is an arithmetic number, because the mean of its divisors is an integer number (911920105).

Almost surely, 2^1823840209 is an apocalyptic number.

It is an amenable number.

1823840209 is a deficient number, since it is larger than the sum of its proper divisors (1).

1823840209 is an equidigital number, since it uses as much as digits as its factorization.

1823840209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 27648, while the sum is 37.

The square root of 1823840209 is about 42706.4422423596. The cubic root of 1823840209 is about 1221.7872686656.

The spelling of 1823840209 in words is "one billion, eight hundred twenty-three million, eight hundred forty thousand, two hundred nine".