1811959 has 2 divisors, whose sum is σ = 1811960. Its totient is φ = 1811958.

The previous prime is 1811939. The next prime is 1811983. The reversal of 1811959 is 9591181.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1811959 - 2¹¹ = 1809911 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1811939) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 905979 + 905980.

It is an arithmetic number, because the mean of its divisors is an integer number (905980).

2^1811959 is an apocalyptic number.

1811959 is a deficient number, since it is larger than the sum of its proper divisors (1).

1811959 is an equidigital number, since it uses as much as digits as its factorization.

1811959 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3240, while the sum is 34.

The square root of 1811959 is about 1346.0902644325. The cubic root of 1811959 is about 121.9128419855.

The spelling of 1811959 in words is "one million, eight hundred eleven thousand, nine hundred fifty-nine".