16521449 has 4 divisors (see below), whose sum is σ = 18881664. Its totient is φ = 14161236.

The previous prime is 16521443. The next prime is 16521451. The reversal of 16521449 is 94412561.

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.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16521449 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (16521443) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1180097 + ... + 1180110.

It is an arithmetic number, because the mean of its divisors is an integer number (4720416).

Almost surely, 2^16521449 is an apocalyptic number.

It is an amenable number.

16521449 is a deficient number, since it is larger than the sum of its proper divisors (2360215).

16521449 is an equidigital number, since it uses as much as digits as its factorization.

16521449 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2360214.

The product of its digits is 8640, while the sum is 32.

The square root of 16521449 is about 4064.6585342437. The cubic root of 16521449 is about 254.6924345137.

The spelling of 16521449 in words is "sixteen million, five hundred twenty-one thousand, four hundred forty-nine".