21301045 has 4 divisors (see below), whose sum is σ = 25561260. Its totient is φ = 17040832.

The previous prime is 21301043. The next prime is 21301057. The reversal of 21301045 is 54010312.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 10712529 + 10588516 = 3273^2 + 3254^2 .

It is a cyclic number.

It is not a de Polignac number, because 21301045 - 2¹ = 21301043 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21301043) 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 3 ways as a sum of consecutive naturals, for example, 2130100 + ... + 2130109.

It is an arithmetic number, because the mean of its divisors is an integer number (6390315).

Almost surely, 2^21301045 is an apocalyptic number.

It is an amenable number.

21301045 is a deficient number, since it is larger than the sum of its proper divisors (4260215).

21301045 is an equidigital number, since it uses as much as digits as its factorization.

21301045 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4260214.

The product of its (nonzero) digits is 120, while the sum is 16.

The square root of 21301045 is about 4615.3055153478. The cubic root of 21301045 is about 277.2045173399.

Adding to 21301045 its reverse (54010312), we get a palindrome (75311357).

The spelling of 21301045 in words is "twenty-one million, three hundred one thousand, forty-five".