18646428 has 12 divisors (see below), whose sum is σ = 43508360. Its totient is φ = 6215472.

The previous prime is 18646427. The next prime is 18646457. The reversal of 18646428 is 82464681.

It is a tau number, because it is divible by the number of its divisors (12).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18646423) 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, 776923 + ... + 776946.

Almost surely, 2^18646428 is an apocalyptic number.

It is an amenable number.

18646428 is an abundant number, since it is smaller than the sum of its proper divisors (24861932).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18646428 is a wasteful number, since it uses less digits than its factorization.

18646428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1553876 (or 1553874 counting only the distinct ones).

The product of its digits is 73728, while the sum is 39.

The square root of 18646428 is about 4318.1509931914. The cubic root of 18646428 is about 265.1745758428.

The spelling of 18646428 in words is "eighteen million, six hundred forty-six thousand, four hundred twenty-eight".