16520789 has 4 divisors (see below), whose sum is σ = 16832556. Its totient is φ = 16209024.

The previous prime is 16520783. The next prime is 16520797. The reversal of 16520789 is 98702561.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 98702561 = 17 ⋅5806033.

It can be written as a sum of positive squares in 2 ways, for example, as 6848689 + 9672100 = 2617^2 + 3110^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16520789 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 (16520783) 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, 155804 + ... + 155909.

It is an arithmetic number, because the mean of its divisors is an integer number (4208139).

Almost surely, 2^16520789 is an apocalyptic number.

It is an amenable number.

16520789 is a deficient number, since it is larger than the sum of its proper divisors (311767).

16520789 is an equidigital number, since it uses as much as digits as its factorization.

16520789 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 311766.

The product of its (nonzero) digits is 30240, while the sum is 38.

The square root of 16520789 is about 4064.5773458012. The cubic root of 16520789 is about 254.6890429781.

The spelling of 16520789 in words is "sixteen million, five hundred twenty thousand, seven hundred eighty-nine".