16438649 has 4 divisors (see below), whose sum is σ = 16968960. Its totient is φ = 15908340.

The previous prime is 16438637. The next prime is 16438657. The reversal of 16438649 is 94683461.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 94683461 = 347 ⋅272863.

It is a cyclic number.

It is not a de Polignac number, because 16438649 - 2⁸ = 16438393 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16438349) 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, 265109 + ... + 265170.

It is an arithmetic number, because the mean of its divisors is an integer number (4242240).

Almost surely, 2^16438649 is an apocalyptic number.

It is an amenable number.

16438649 is a deficient number, since it is larger than the sum of its proper divisors (530311).

16438649 is an equidigital number, since it uses as much as digits as its factorization.

16438649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 530310.

The product of its digits is 124416, while the sum is 41.

The square root of 16438649 is about 4054.4603833309. The cubic root of 16438649 is about 254.2662438576.

The spelling of 16438649 in words is "sixteen million, four hundred thirty-eight thousand, six hundred forty-nine".