16623505 has 4 divisors (see below), whose sum is σ = 19948212. Its totient is φ = 13298800.

The previous prime is 16623493. The next prime is 16623511. The reversal of 16623505 is 50532661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 50532661 = 47 ⋅1075163.

It can be written as a sum of positive squares in 2 ways, for example, as 3721041 + 12902464 = 1929^2 + 3592^2 .

It is not a de Polignac number, because 16623505 - 2⁷ = 16623377 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1662346 + ... + 1662355.

It is an arithmetic number, because the mean of its divisors is an integer number (4987053).

Almost surely, 2^16623505 is an apocalyptic number.

It is an amenable number.

16623505 is a deficient number, since it is larger than the sum of its proper divisors (3324707).

16623505 is an equidigital number, since it uses as much as digits as its factorization.

16623505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3324706.

The product of its (nonzero) digits is 5400, while the sum is 28.

The square root of 16623505 is about 4077.1932747909. The cubic root of 16623505 is about 255.2157855642.

The spelling of 16623505 in words is "sixteen million, six hundred twenty-three thousand, five hundred five".