18280421 has 8 divisors (see below), whose sum is σ = 18924288. Its totient is φ = 17640000.

The previous prime is 18280417. The next prime is 18280429. The reversal of 18280421 is 12408281.

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 18280421 - 2² = 18280417 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 (18280429) 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, 14621 + ... + 15821.

It is an arithmetic number, because the mean of its divisors is an integer number (2365536).

Almost surely, 2^18280421 is an apocalyptic number.

It is an amenable number.

18280421 is a deficient number, since it is larger than the sum of its proper divisors (643867).

18280421 is a wasteful number, since it uses less digits than its factorization.

18280421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1723.

The product of its (nonzero) digits is 1024, while the sum is 26.

The square root of 18280421 is about 4275.5608988763. The cubic root of 18280421 is about 263.4280787452.

The spelling of 18280421 in words is "eighteen million, two hundred eighty thousand, four hundred twenty-one".