1820709823 has 2 divisors, whose sum is σ = 1820709824. Its totient is φ = 1820709822.

The previous prime is 1820709811. The next prime is 1820709853. The reversal of 1820709823 is 3289070281.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1820709823 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1820709853) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 910354911 + 910354912.

It is an arithmetic number, because the mean of its divisors is an integer number (910354912).

Almost surely, 2^1820709823 is an apocalyptic number.

1820709823 is a deficient number, since it is larger than the sum of its proper divisors (1).

1820709823 is an equidigital number, since it uses as much as digits as its factorization.

1820709823 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 48384, while the sum is 40.

The square root of 1820709823 is about 42669.7764582849. The cubic root of 1820709823 is about 1221.0878550488.

The spelling of 1820709823 in words is "one billion, eight hundred twenty million, seven hundred nine thousand, eight hundred twenty-three".