16984561 has 4 divisors (see below), whose sum is σ = 18528624. Its totient is φ = 15440500.

The previous prime is 16984523. The next prime is 16984571. The reversal of 16984561 is 16548961.

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 not a de Polignac number, because 16984561 - 2⁹ = 16984049 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16984571) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 772015 + ... + 772036.

It is an arithmetic number, because the mean of its divisors is an integer number (4632156).

Almost surely, 2^16984561 is an apocalyptic number.

16984561 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

16984561 is a deficient number, since it is larger than the sum of its proper divisors (1544063).

16984561 is a wasteful number, since it uses less digits than its factorization.

16984561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1544062.

The product of its digits is 51840, while the sum is 40.

The square root of 16984561 is about 4121.2329465829. The cubic root of 16984561 is about 257.0502962420.

Subtracting from 16984561 its reverse (16548961), we obtain a square (435600 = 660²).

The spelling of 16984561 in words is "sixteen million, nine hundred eighty-four thousand, five hundred sixty-one".