16509423 has 48 divisors (see below), whose sum is σ = 28235520. Its totient is φ = 8515584.

The previous prime is 16509421. The next prime is 16509433. The reversal of 16509423 is 32490561.

It is not a de Polignac number, because 16509423 - 2¹ = 16509421 is a prime.

It is a super-2 number, since 2×16509423² = 545122095585858, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16509421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 64111 + ... + 64367.

It is an arithmetic number, because the mean of its divisors is an integer number (588240).

Almost surely, 2^16509423 is an apocalyptic number.

16509423 is a deficient number, since it is larger than the sum of its proper divisors (11726097).

16509423 is a wasteful number, since it uses less digits than its factorization.

16509423 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 316 (or 309 counting only the distinct ones).

The product of its (nonzero) digits is 6480, while the sum is 30.

The square root of 16509423 is about 4063.1789278839. The cubic root of 16509423 is about 254.6306224476.

Adding to 16509423 its reverse (32490561), we get a palindrome (48999984).

The spelling of 16509423 in words is "sixteen million, five hundred nine thousand, four hundred twenty-three".