190000009 has 4 divisors (see below), whose sum is σ = 190205460. Its totient is φ = 189794560.

The previous prime is 190000003. The next prime is 190000021. The reversal of 190000009 is 900000091.

190000009 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 900000091 = 31 ⋅29032261.

It can be written as a sum of positive squares in 2 ways, for example, as 24800400 + 165199609 = 4980^2 + 12853^2 .

It is a cyclic number.

It is not a de Polignac number, because 190000009 - 2¹¹ = 189997961 is a prime.

It is a super-2 number, since 2×190000009² = 72200006840000162, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (190000003) 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, 101332 + ... + 103189.

It is an arithmetic number, because the mean of its divisors is an integer number (47551365).

Almost surely, 2^190000009 is an apocalyptic number.

It is an amenable number.

190000009 is a deficient number, since it is larger than the sum of its proper divisors (205451).

190000009 is an equidigital number, since it uses as much as digits as its factorization.

190000009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 205450.

The product of its (nonzero) digits is 81, while the sum is 19.

The square root of 190000009 is about 13784.0490785545. The cubic root of 190000009 is about 574.8897169717.

The spelling of 190000009 in words is "one hundred ninety million, nine", and thus it is an aban number.