21340221221 has 8 divisors (see below), whose sum is σ = 23288040000. Its totient is φ = 19393702240.

The previous prime is 21340221191. The next prime is 21340221239. The reversal of 21340221221 is 12212204312.

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

It is not a de Polignac number, because 21340221221 - 2¹⁰ = 21340220197 is a prime.

It is a super-3 number, since 3×21340221221³ (a number of 32 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21340221193 and 21340221202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21340221281) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 290456 + ... + 356433.

It is an arithmetic number, because the mean of its divisors is an integer number (2911005000).

Almost surely, 2^21340221221 is an apocalyptic number.

It is an amenable number.

21340221221 is a deficient number, since it is larger than the sum of its proper divisors (1947818779).

21340221221 is a wasteful number, since it uses less digits than its factorization.

21340221221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 649899.

The product of its (nonzero) digits is 384, while the sum is 20.

Adding to 21340221221 its reverse (12212204312), we get a palindrome (33552425533).

The spelling of 21340221221 in words is "twenty-one billion, three hundred forty million, two hundred twenty-one thousand, two hundred twenty-one".