16431109 has 4 divisors (see below), whose sum is σ = 16480204. Its totient is φ = 16382016.

The previous prime is 16431101. The next prime is 16431127. The reversal of 16431109 is 90113461.

16431109 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: 90113461 = 109 ⋅826729.

It can be written as a sum of positive squares in 2 ways, for example, as 3629025 + 12802084 = 1905^2 + 3578^2 .

It is a cyclic number.

It is not a de Polignac number, because 16431109 - 2³ = 16431101 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 (16431101) 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, 24042 + ... + 24715.

It is an arithmetic number, because the mean of its divisors is an integer number (4120051).

Almost surely, 2^16431109 is an apocalyptic number.

It is an amenable number.

16431109 is a deficient number, since it is larger than the sum of its proper divisors (49095).

16431109 is an equidigital number, since it uses as much as digits as its factorization.

16431109 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49094.

The product of its (nonzero) digits is 648, while the sum is 25.

The square root of 16431109 is about 4053.5304365454. The cubic root of 16431109 is about 254.2273627088.

The spelling of 16431109 in words is "sixteen million, four hundred thirty-one thousand, one hundred nine".