18503421 has 8 divisors (see below), whose sum is σ = 25522080. Its totient is φ = 11910192.

The previous prime is 18503399. The next prime is 18503437. The reversal of 18503421 is 12430581.

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

It is not a de Polignac number, because 18503421 - 2¹⁰ = 18502397 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 18503391 and 18503400.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18503461) 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, 106255 + ... + 106428.

It is an arithmetic number, because the mean of its divisors is an integer number (3190260).

Almost surely, 2^18503421 is an apocalyptic number.

It is an amenable number.

18503421 is a deficient number, since it is larger than the sum of its proper divisors (7018659).

18503421 is a wasteful number, since it uses less digits than its factorization.

18503421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 212715.

The product of its (nonzero) digits is 960, while the sum is 24.

The square root of 18503421 is about 4301.5602983104. The cubic root of 18503421 is about 264.4949249970.

The spelling of 18503421 in words is "eighteen million, five hundred three thousand, four hundred twenty-one".