21301235 has 4 divisors (see below), whose sum is σ = 25561488. Its totient is φ = 17040984.

The previous prime is 21301229. The next prime is 21301253. The reversal of 21301235 is 53210312.

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

It is a cyclic number.

It is not a de Polignac number, because 21301235 - 2⁴ = 21301219 is a prime.

It is a super-2 number, since 2×21301235² = 907485225050450, which contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2130119 + ... + 2130128.

It is an arithmetic number, because the mean of its divisors is an integer number (6390372).

Almost surely, 2^21301235 is an apocalyptic number.

21301235 is a deficient number, since it is larger than the sum of its proper divisors (4260253).

21301235 is an equidigital number, since it uses as much as digits as its factorization.

21301235 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4260252.

The product of its (nonzero) digits is 180, while the sum is 17.

The square root of 21301235 is about 4615.3260989880. The cubic root of 21301235 is about 277.2053415358.

Adding to 21301235 its reverse (53210312), we get a palindrome (74511547).

The spelling of 21301235 in words is "twenty-one million, three hundred one thousand, two hundred thirty-five".