21315302241 has 4 divisors (see below), whose sum is σ = 28420402992. Its totient is φ = 14210201492.

The previous prime is 21315302227. The next prime is 21315302251. The reversal of 21315302241 is 14220351312.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21315302241 - 2⁹ = 21315301729 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21315302201) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3552550371 + ... + 3552550376.

It is an arithmetic number, because the mean of its divisors is an integer number (7105100748).

Almost surely, 2^21315302241 is an apocalyptic number.

It is an amenable number.

21315302241 is a deficient number, since it is larger than the sum of its proper divisors (7105100751).

21315302241 is an equidigital number, since it uses as much as digits as its factorization.

21315302241 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7105100750.

The product of its (nonzero) digits is 1440, while the sum is 24.

Adding to 21315302241 its reverse (14220351312), we get a palindrome (35535653553).

The spelling of 21315302241 in words is "twenty-one billion, three hundred fifteen million, three hundred two thousand, two hundred forty-one".