17221421 has 8 divisors (see below), whose sum is σ = 19919424. Its totient is φ = 14582880.

The previous prime is 17221417. The next prime is 17221427. The reversal of 17221421 is 12412271.

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 17221421 - 2² = 17221417 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 17221393 and 17221402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (17221427) 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, 14240 + ... + 15401.

It is an arithmetic number, because the mean of its divisors is an integer number (2489928).

Almost surely, 2^17221421 is an apocalyptic number.

It is an amenable number.

17221421 is a deficient number, since it is larger than the sum of its proper divisors (2698003).

17221421 is an equidigital number, since it uses as much as digits as its factorization.

17221421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29731.

The product of its digits is 224, while the sum is 20.

The square root of 17221421 is about 4149.8699979638. The cubic root of 17221421 is about 258.2396917167.

Adding to 17221421 its reverse (12412271), we get a palindrome (29633692).

The spelling of 17221421 in words is "seventeen million, two hundred twenty-one thousand, four hundred twenty-one".