18671021 has 8 divisors (see below), whose sum is σ = 19353600. Its totient is φ = 17993520.

The previous prime is 18671011. The next prime is 18671047. The reversal of 18671021 is 12017681.

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 18671021 - 2²² = 14476717 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 (18671011) 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, 7220 + ... + 9458.

It is an arithmetic number, because the mean of its divisors is an integer number (2419200).

Almost surely, 2^18671021 is an apocalyptic number.

It is an amenable number.

18671021 is a deficient number, since it is larger than the sum of its proper divisors (682579).

18671021 is a wasteful number, since it uses less digits than its factorization.

18671021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2539.

The product of its (nonzero) digits is 672, while the sum is 26.

The square root of 18671021 is about 4320.9976857203. The cubic root of 18671021 is about 265.2911052817.

The spelling of 18671021 in words is "eighteen million, six hundred seventy-one thousand, twenty-one".