21013440321 has 8 divisors (see below), whose sum is σ = 28027362784. Its totient is φ = 14004239040.

The previous prime is 21013440311. The next prime is 21013440341. The reversal of 21013440321 is 12304431012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21013440321 - 2¹⁰ = 21013439297 is a prime.

It is a super-3 number, since 3×21013440321³ (a number of 32 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21013440311) 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 7 ways as a sum of consecutive naturals, for example, 1169896 + ... + 1187721.

It is an arithmetic number, because the mean of its divisors is an integer number (3503420348).

Almost surely, 2^21013440321 is an apocalyptic number.

It is an amenable number.

21013440321 is a deficient number, since it is larger than the sum of its proper divisors (7013922463).

21013440321 is a wasteful number, since it uses less digits than its factorization.

21013440321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2360591.

The product of its (nonzero) digits is 576, while the sum is 21.

Adding to 21013440321 its reverse (12304431012), we get a palindrome (33317871333).

The spelling of 21013440321 in words is "twenty-one billion, thirteen million, four hundred forty thousand, three hundred twenty-one".