18908671 has 4 divisors (see below), whose sum is σ = 19053144. Its totient is φ = 18764200.

The previous prime is 18908663. The next prime is 18908693. The reversal of 18908671 is 17680981.

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 18908671 - 2³ = 18908663 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 (18908621) 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, 72040 + ... + 72301.

It is an arithmetic number, because the mean of its divisors is an integer number (4763286).

Almost surely, 2^18908671 is an apocalyptic number.

18908671 is a deficient number, since it is larger than the sum of its proper divisors (144473).

18908671 is a wasteful number, since it uses less digits than its factorization.

18908671 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 144472.

The product of its (nonzero) digits is 24192, while the sum is 40.

The square root of 18908671 is about 4348.4101692458. The cubic root of 18908671 is about 266.4119298270.

The spelling of 18908671 in words is "eighteen million, nine hundred eight thousand, six hundred seventy-one".