16638313 has 4 divisors (see below), whose sum is σ = 16809940. Its totient is φ = 16466688.

The previous prime is 16638301. The next prime is 16638317. The reversal of 16638313 is 31383661.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 6953769 + 9684544 = 2637^2 + 3112^2 .

It is a cyclic number.

It is not a de Polignac number, because 16638313 - 2¹⁷ = 16507241 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16638317) 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, 85668 + ... + 85861.

It is an arithmetic number, because the mean of its divisors is an integer number (4202485).

Almost surely, 2^16638313 is an apocalyptic number.

It is an amenable number.

16638313 is a deficient number, since it is larger than the sum of its proper divisors (171627).

16638313 is an equidigital number, since it uses as much as digits as its factorization.

16638313 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 171626.

The product of its digits is 7776, while the sum is 31.

The square root of 16638313 is about 4079.0088256830. The cubic root of 16638313 is about 255.2915440308.

The spelling of 16638313 in words is "sixteen million, six hundred thirty-eight thousand, three hundred thirteen".