1909121603 has 2 divisors, whose sum is σ = 1909121604. Its totient is φ = 1909121602.

The previous prime is 1909121569. The next prime is 1909121633. The reversal of 1909121603 is 3061219091.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1909121603 - 2²⁸ = 1640686147 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1909121603.

It is not a weakly prime, because it can be changed into another prime (1909121633) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 954560801 + 954560802.

It is an arithmetic number, because the mean of its divisors is an integer number (954560802).

Almost surely, 2^1909121603 is an apocalyptic number.

1909121603 is a deficient number, since it is larger than the sum of its proper divisors (1).

1909121603 is an equidigital number, since it uses as much as digits as its factorization.

1909121603 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2916, while the sum is 32.

The square root of 1909121603 is about 43693.4961178434. The cubic root of 1909121603 is about 1240.5412142745.

The spelling of 1909121603 in words is "one billion, nine hundred nine million, one hundred twenty-one thousand, six hundred three".