16638245 has 8 divisors (see below), whose sum is σ = 21501816. Its totient is φ = 12286656.

The previous prime is 16638221. The next prime is 16638247. The reversal of 16638245 is 54283661.

It can be written as a sum of positive squares in 4 ways, for example, as 2455489 + 14182756 = 1567^2 + 3766^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 16638245 - 2⁸ = 16637989 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16638247) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 127922 + ... + 128051.

It is an arithmetic number, because the mean of its divisors is an integer number (2687727).

Almost surely, 2^16638245 is an apocalyptic number.

It is an amenable number.

16638245 is a deficient number, since it is larger than the sum of its proper divisors (4863571).

16638245 is a wasteful number, since it uses less digits than its factorization.

16638245 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 255991.

The product of its digits is 34560, while the sum is 35.

The square root of 16638245 is about 4079.0004903162. Note that the first 3 decimals coincide. The cubic root of 16638245 is about 255.2911962422.

The spelling of 16638245 in words is "sixteen million, six hundred thirty-eight thousand, two hundred forty-five".