18468921 has 8 divisors (see below), whose sum is σ = 24717184. Its totient is φ = 12266640.

The previous prime is 18468917. The next prime is 18468941. The reversal of 18468921 is 12986481.

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

It is not a de Polignac number, because 18468921 - 2² = 18468917 is a prime.

It is a super-2 number, since 2×18468921² = 682202085808482, which contains 22 as substring.

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 18468921.

It is not an unprimeable number, because it can be changed into a prime (18468941) 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, 10546 + ... + 12171.

It is an arithmetic number, because the mean of its divisors is an integer number (3089648).

Almost surely, 2^18468921 is an apocalyptic number.

It is an amenable number.

18468921 is a deficient number, since it is larger than the sum of its proper divisors (6248263).

18468921 is a wasteful number, since it uses less digits than its factorization.

18468921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22991.

The product of its digits is 27648, while the sum is 39.

The square root of 18468921 is about 4297.5482545284. The cubic root of 18468921 is about 264.3304373582.

It can be divided in two parts, 18468 and 921, that multiplied together give a triangular number (17009028 = T₅₈₃₂).

The spelling of 18468921 in words is "eighteen million, four hundred sixty-eight thousand, nine hundred twenty-one".