21303105 has 8 divisors (see below), whose sum is σ = 34084992. Its totient is φ = 11361648.

The previous prime is 21303059. The next prime is 21303109. The reversal of 21303105 is 50130312.

It is a happy number.

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

It is not a de Polignac number, because 21303105 - 2⁶ = 21303041 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (15), and also a Moran number because the ratio is a prime number: 1420207 = 21303105 / (2 + 1 + 3 + 0 + 3 + 1 + 0 + 5).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21303109) 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, 710089 + ... + 710118.

It is an arithmetic number, because the mean of its divisors is an integer number (4260624).

Almost surely, 2^21303105 is an apocalyptic number.

It is an amenable number.

21303105 is a deficient number, since it is larger than the sum of its proper divisors (12781887).

21303105 is a wasteful number, since it uses less digits than its factorization.

21303105 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1420215.

The product of its (nonzero) digits is 90, while the sum is 15.

The square root of 21303105 is about 4615.5286804439. The cubic root of 21303105 is about 277.2134530971.

Adding to 21303105 its reverse (50130312), we get a palindrome (71433417).

The spelling of 21303105 in words is "twenty-one million, three hundred three thousand, one hundred five".