21001303 has 8 divisors (see below), whose sum is σ = 21702816. Its totient is φ = 20311200.

The previous prime is 21001247. The next prime is 21001319. The reversal of 21001303 is 30310012.

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 21001303 - 2¹³ = 20993111 is a prime.

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 21001303.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21001703) 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, 973 + ... + 6553.

It is an arithmetic number, because the mean of its divisors is an integer number (2712852).

Almost surely, 2^21001303 is an apocalyptic number.

21001303 is a deficient number, since it is larger than the sum of its proper divisors (701513).

21001303 is an equidigital number, since it uses as much as digits as its factorization.

21001303 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5705.

The product of its (nonzero) digits is 18, while the sum is 10.

The square root of 21001303 is about 4582.7178617061. The cubic root of 21001303 is about 275.8981236760.

Adding to 21001303 its reverse (30310012), we get a palindrome (51311315).

It can be divided in two parts, 2100 and 1303, that added together give a triangular number (3403 = T₈₂).

The spelling of 21001303 in words is "twenty-one million, one thousand, three hundred three".