16122409 has 4 divisors (see below), whose sum is σ = 17070804. Its totient is φ = 15174016.

The previous prime is 16122401. The next prime is 16122413. The reversal of 16122409 is 90422161.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 90422161 = 59 ⋅1532579.

It can be written as a sum of positive squares in 2 ways, for example, as 4528384 + 11594025 = 2128^2 + 3405^2 .

It is a cyclic number.

It is not a de Polignac number, because 16122409 - 2³ = 16122401 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16122401) 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, 474172 + ... + 474205.

It is an arithmetic number, because the mean of its divisors is an integer number (4267701).

Almost surely, 2^16122409 is an apocalyptic number.

It is an amenable number.

16122409 is a deficient number, since it is larger than the sum of its proper divisors (948395).

16122409 is an equidigital number, since it uses as much as digits as its factorization.

16122409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 948394.

The product of its (nonzero) digits is 864, while the sum is 25.

The square root of 16122409 is about 4015.2719708632. The cubic root of 16122409 is about 252.6251851231.

The spelling of 16122409 in words is "sixteen million, one hundred twenty-two thousand, four hundred nine".