16645441 has 4 divisors (see below), whose sum is σ = 16695172. Its totient is φ = 16595712.

The previous prime is 16645427. The next prime is 16645469. The reversal of 16645441 is 14454661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 14454661 = 13 ⋅1111897.

It can be written as a sum of positive squares in 2 ways, for example, as 9241600 + 7403841 = 3040^2 + 2721^2 .

It is a 4-Lehmer number, since φ(16645441) divides (16645441-1)⁴.

It is a cyclic number.

It is not a de Polignac number, because 16645441 - 2¹³ = 16637249 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16645411) 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, 24360 + ... + 25033.

It is an arithmetic number, because the mean of its divisors is an integer number (4173793).

Almost surely, 2^16645441 is an apocalyptic number.

It is an amenable number.

16645441 is a deficient number, since it is larger than the sum of its proper divisors (49731).

16645441 is an equidigital number, since it uses as much as digits as its factorization.

16645441 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49730.

The product of its digits is 11520, while the sum is 31.

The square root of 16645441 is about 4079.8824737975. The cubic root of 16645441 is about 255.3279952088.

The spelling of 16645441 in words is "sixteen million, six hundred forty-five thousand, four hundred forty-one".