18671671 has 4 divisors (see below), whose sum is σ = 18988200. Its totient is φ = 18355144.

The previous prime is 18671663. The next prime is 18671677. The reversal of 18671671 is 17617681.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 17617681 = 2731 ⋅6451.

It is a cyclic number.

It is not a de Polignac number, because 18671671 - 2³ = 18671663 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18671671.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18671677) 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, 158176 + ... + 158293.

It is an arithmetic number, because the mean of its divisors is an integer number (4747050).

Almost surely, 2^18671671 is an apocalyptic number.

18671671 is a deficient number, since it is larger than the sum of its proper divisors (316529).

18671671 is an equidigital number, since it uses as much as digits as its factorization.

18671671 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 316528.

The product of its digits is 14112, while the sum is 37.

The square root of 18671671 is about 4321.0728991768. The cubic root of 18671671 is about 265.2941837996.

The spelling of 18671671 in words is "eighteen million, six hundred seventy-one thousand, six hundred seventy-one".