1909489 has 2 divisors, whose sum is σ = 1909490. Its totient is φ = 1909488.

The previous prime is 1909487. The next prime is 1909513. The reversal of 1909489 is 9849091.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1361889 + 547600 = 1167^2 + 740^2 .

It is a cyclic number.

It is not a de Polignac number, because 1909489 - 2¹ = 1909487 is a prime.

It is a super-2 number, since 2×1909489² = 7292296482242, which contains 22 as substring.

Together with 1909487, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (1909487) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 954744 + 954745.

It is an arithmetic number, because the mean of its divisors is an integer number (954745).

2^1909489 is an apocalyptic number.

It is an amenable number.

1909489 is a deficient number, since it is larger than the sum of its proper divisors (1).

1909489 is an equidigital number, since it uses as much as digits as its factorization.

1909489 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 23328, while the sum is 40.

The square root of 1909489 is about 1381.8426104300. The cubic root of 1909489 is about 124.0620786975.

The spelling of 1909489 in words is "one million, nine hundred nine thousand, four hundred eighty-nine".