21122351321 has 4 divisors (see below), whose sum is σ = 21210729600. Its totient is φ = 21033973044.

The previous prime is 21122351249. The next prime is 21122351351. The reversal of 21122351321 is 12315322112.

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 21122351321 - 2²⁶ = 21055242457 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21122351351) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 44188781 + ... + 44189258.

It is an arithmetic number, because the mean of its divisors is an integer number (5302682400).

Almost surely, 2^21122351321 is an apocalyptic number.

It is an amenable number.

21122351321 is a deficient number, since it is larger than the sum of its proper divisors (88378279).

21122351321 is an equidigital number, since it uses as much as digits as its factorization.

21122351321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 88378278.

The product of its digits is 720, while the sum is 23.

Adding to 21122351321 its reverse (12315322112), we get a palindrome (33437673433).

The spelling of 21122351321 in words is "twenty-one billion, one hundred twenty-two million, three hundred fifty-one thousand, three hundred twenty-one".