18861671 has 8 divisors (see below), whose sum is σ = 19588224. Its totient is φ = 18142560.

The previous prime is 18861643. The next prime is 18861673. The reversal of 18861671 is 17616881.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18861671 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 (18861673) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3605 + ... + 7121.

It is an arithmetic number, because the mean of its divisors is an integer number (2448528).

Almost surely, 2^18861671 is an apocalyptic number.

18861671 is a deficient number, since it is larger than the sum of its proper divisors (726553).

18861671 is a wasteful number, since it uses less digits than its factorization.

18861671 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3721.

The product of its digits is 16128, while the sum is 38.

The square root of 18861671 is about 4343.0025328107. The cubic root of 18861671 is about 266.1910126695.

The spelling of 18861671 in words is "eighteen million, eight hundred sixty-one thousand, six hundred seventy-one".