21242410321 has 4 divisors (see below), whose sum is σ = 23173538544. Its totient is φ = 19311282100.

The previous prime is 21242410297. The next prime is 21242410331. The reversal of 21242410321 is 12301424212.

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 not a de Polignac number, because 21242410321 - 2¹⁵ = 21242377553 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21242410292 and 21242410301.

It is not an unprimeable number, because it can be changed into a prime (21242410331) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 965564095 + ... + 965564116.

It is an arithmetic number, because the mean of its divisors is an integer number (5793384636).

Almost surely, 2^21242410321 is an apocalyptic number.

It is an amenable number.

21242410321 is a deficient number, since it is larger than the sum of its proper divisors (1931128223).

21242410321 is a wasteful number, since it uses less digits than its factorization.

21242410321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1931128222.

The product of its (nonzero) digits is 768, while the sum is 22.

Adding to 21242410321 its reverse (12301424212), we get a palindrome (33543834533).

The spelling of 21242410321 in words is "twenty-one billion, two hundred forty-two million, four hundred ten thousand, three hundred twenty-one".