16621366 has 4 divisors (see below), whose sum is σ = 24932052. Its totient is φ = 8310682.

The previous prime is 16621361. The next prime is 16621391. The reversal of 16621366 is 66312661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 66312661 = 101 ⋅656561.

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 congruent number.

It is not an unprimeable number, because it can be changed into a prime (16621361) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4155340 + ... + 4155343.

It is an arithmetic number, because the mean of its divisors is an integer number (6233013).

Almost surely, 2^16621366 is an apocalyptic number.

16621366 is a deficient number, since it is larger than the sum of its proper divisors (8310686).

16621366 is an equidigital number, since it uses as much as digits as its factorization.

16621366 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8310685.

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

The square root of 16621366 is about 4076.9309535483. The cubic root of 16621366 is about 255.2048386153.

The spelling of 16621366 in words is "sixteen million, six hundred twenty-one thousand, three hundred sixty-six".