1009181909 has 4 divisors (see below), whose sum is σ = 1011460416. Its totient is φ = 1006903404.

The previous prime is 1009181893. The next prime is 1009181911. The reversal of 1009181909 is 9091819001.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 9091819001 = 5113 ⋅1778177.

It is a cyclic number.

It is not a de Polignac number, because 1009181909 - 2⁴ = 1009181893 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 (1009181959) 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, 1138589 + ... + 1139474.

It is an arithmetic number, because the mean of its divisors is an integer number (252865104).

Almost surely, 2^1009181909 is an apocalyptic number.

It is an amenable number.

1009181909 is a deficient number, since it is larger than the sum of its proper divisors (2278507).

1009181909 is an equidigital number, since it uses as much as digits as its factorization.

1009181909 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2278506.

The product of its (nonzero) digits is 5832, while the sum is 38.

The square root of 1009181909 is about 31767.6235969894. The cubic root of 1009181909 is about 1003.0513163322.

The spelling of 1009181909 in words is "one billion, nine million, one hundred eighty-one thousand, nine hundred nine".