21315241355321 has 4 divisors (see below), whose sum is σ = 21315352678032. Its totient is φ = 21315130032612.

The previous prime is 21315241355297. The next prime is 21315241355323. The reversal of 21315241355321 is 12355314251312.

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 21315241355321 - 2³⁴ = 21298061486137 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21315241355323) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 55373651 + ... + 55757256.

It is an arithmetic number, because the mean of its divisors is an integer number (5328838169508).

Almost surely, 2^{21315241355321} is an apocalyptic number.

It is an amenable number.

21315241355321 is a deficient number, since it is larger than the sum of its proper divisors (111322711).

21315241355321 is a wasteful number, since it uses less digits than its factorization.

21315241355321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 111322710.

The product of its digits is 108000, while the sum is 38.

The spelling of 21315241355321 in words is "twenty-one trillion, three hundred fifteen billion, two hundred forty-one million, three hundred fifty-five thousand, three hundred twenty-one".