21303017 has 8 divisors (see below), whose sum is σ = 21864480. Its totient is φ = 20744640.

The previous prime is 21303011. The next prime is 21303031. The reversal of 21303017 is 71030312.

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 21303017 - 2¹⁴ = 21286633 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21302986 and 21303004.

It is not an unprimeable number, because it can be changed into a prime (21303011) 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, 20609 + ... + 21617.

It is an arithmetic number, because the mean of its divisors is an integer number (2733060).

Almost surely, 2^21303017 is an apocalyptic number.

It is an amenable number.

21303017 is a deficient number, since it is larger than the sum of its proper divisors (561463).

21303017 is a wasteful number, since it uses less digits than its factorization.

21303017 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1543.

The product of its (nonzero) digits is 126, while the sum is 17.

The square root of 21303017 is about 4615.5191473983. The cubic root of 21303017 is about 277.2130713872.

Adding to 21303017 its reverse (71030312), we get a palindrome (92333329).

The spelling of 21303017 in words is "twenty-one million, three hundred three thousand, seventeen".