18672661 has 8 divisors (see below), whose sum is σ = 21412160. Its totient is φ = 15951168.

The previous prime is 18672653. The next prime is 18672691. The reversal of 18672661 is 16627681.

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

It is a cyclic number.

It is not a de Polignac number, because 18672661 - 2³ = 18672653 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18672661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18672601) 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, 2196 + ... + 6493.

It is an arithmetic number, because the mean of its divisors is an integer number (2676520).

Almost surely, 2^18672661 is an apocalyptic number.

It is an amenable number.

18672661 is a deficient number, since it is larger than the sum of its proper divisors (2739499).

18672661 is an equidigital number, since it uses as much as digits as its factorization.

18672661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9003.

The product of its digits is 24192, while the sum is 37.

The square root of 18672661 is about 4321.1874525413. The cubic root of 18672661 is about 265.2988724819.

The spelling of 18672661 in words is "eighteen million, six hundred seventy-two thousand, six hundred sixty-one".