18648647 has 4 divisors (see below), whose sum is σ = 18911376. Its totient is φ = 18385920.

The previous prime is 18648601. The next prime is 18648659. The reversal of 18648647 is 74684681.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 18648647 - 2⁶ = 18648583 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18648598 and 18648607.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18648697) 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, 131258 + ... + 131399.

It is an arithmetic number, because the mean of its divisors is an integer number (4727844).

Almost surely, 2^18648647 is an apocalyptic number.

18648647 is a deficient number, since it is larger than the sum of its proper divisors (262729).

18648647 is an equidigital number, since it uses as much as digits as its factorization.

18648647 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 262728.

The product of its digits is 258048, while the sum is 44.

The square root of 18648647 is about 4318.4079242239. The cubic root of 18648647 is about 265.1850943729.

The spelling of 18648647 in words is "eighteen million, six hundred forty-eight thousand, six hundred forty-seven".