1000001909 has 4 divisors (see below), whose sum is σ = 1009903020. Its totient is φ = 990100800.

The previous prime is 1000001887. The next prime is 1000001917. The reversal of 1000001909 is 9091000001.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9091000001 = 101 ⋅90009901.

It can be written as a sum of positive squares in 2 ways, for example, as 736036900 + 263965009 = 27130^2 + 16247^2 .

It is a cyclic number.

It is not a de Polignac number, because 1000001909 - 2²⁸ = 731566453 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1000001969) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4950404 + ... + 4950605.

It is an arithmetic number, because the mean of its divisors is an integer number (252475755).

Almost surely, 2^1000001909 is an apocalyptic number.

It is an amenable number.

1000001909 is a deficient number, since it is larger than the sum of its proper divisors (9901111).

1000001909 is an equidigital number, since it uses as much as digits as its factorization.

1000001909 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9901110.

The product of its (nonzero) digits is 81, while the sum is 20.

The square root of 1000001909 is about 31622.8067856097. The cubic root of 1000001909 is about 1000.0006363329. Note that the first 3 decimals are identical.

It can be divided in two parts, 1000001 and 909, that multiplied together give a palindrome (909000909).

The spelling of 1000001909 in words is "one billion, one thousand, nine hundred nine".