16656789 has 4 divisors (see below), whose sum is σ = 22209056. Its totient is φ = 11104524.

The previous prime is 16656769. The next prime is 16656791. The reversal of 16656789 is 98765661.

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: 98765661 = 3 ⋅32921887.

It is not a de Polignac number, because 16656789 - 2⁸ = 16656533 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 (16656709) 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, 2776129 + ... + 2776134.

It is an arithmetic number, because the mean of its divisors is an integer number (5552264).

Almost surely, 2^16656789 is an apocalyptic number.

It is an amenable number.

16656789 is a deficient number, since it is larger than the sum of its proper divisors (5552267).

16656789 is an equidigital number, since it uses as much as digits as its factorization.

16656789 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5552266.

The product of its digits is 544320, while the sum is 48.

The square root of 16656789 is about 4081.2729631820. The cubic root of 16656789 is about 255.3860051647.

The spelling of 16656789 in words is "sixteen million, six hundred fifty-six thousand, seven hundred eighty-nine".