16620385 has 4 divisors (see below), whose sum is σ = 19944468. Its totient is φ = 13296304.

The previous prime is 16620361. The next prime is 16620391. The reversal of 16620385 is 58302661.

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 2005056 + 14615329 = 1416^2 + 3823^2 .

It is a cyclic number.

It is not a de Polignac number, because 16620385 - 2⁵ = 16620353 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

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, 1662034 + ... + 1662043.

It is an arithmetic number, because the mean of its divisors is an integer number (4986117).

Almost surely, 2^16620385 is an apocalyptic number.

It is an amenable number.

16620385 is a deficient number, since it is larger than the sum of its proper divisors (3324083).

16620385 is an equidigital number, since it uses as much as digits as its factorization.

16620385 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3324082.

The product of its (nonzero) digits is 8640, while the sum is 31.

The square root of 16620385 is about 4076.8106406847. The cubic root of 16620385 is about 255.1998177509.

The spelling of 16620385 in words is "sixteen million, six hundred twenty thousand, three hundred eighty-five".