18080021 has 8 divisors (see below), whose sum is σ = 18778080. Its totient is φ = 17386992.

The previous prime is 18080011. The next prime is 18080033. The reversal of 18080021 is 12008081.

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 18080021 - 2²² = 13885717 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 18079975 and 18080002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18080011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7106 + ... + 9308.

It is an arithmetic number, because the mean of its divisors is an integer number (2347260).

Almost surely, 2^18080021 is an apocalyptic number.

It is an amenable number.

18080021 is a deficient number, since it is larger than the sum of its proper divisors (698059).

18080021 is a wasteful number, since it uses less digits than its factorization.

18080021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2515.

The product of its (nonzero) digits is 128, while the sum is 20.

The square root of 18080021 is about 4252.0607944854. The cubic root of 18080021 is about 262.4619252411.

The spelling of 18080021 in words is "eighteen million, eighty thousand, twenty-one".