21120323221 has 8 divisors (see below), whose sum is σ = 22240692000. Its totient is φ = 20000831760.

The previous prime is 21120323207. The next prime is 21120323243. The reversal of 21120323221 is 12232302112.

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

It is a cyclic number.

It is not a de Polignac number, because 21120323221 - 2⁹ = 21120322709 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (19).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21120321221) 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, 169615 + ... + 266476.

It is an arithmetic number, because the mean of its divisors is an integer number (2780086500).

Almost surely, 2^21120323221 is an apocalyptic number.

It is an amenable number.

21120323221 is a deficient number, since it is larger than the sum of its proper divisors (1120368779).

21120323221 is a wasteful number, since it uses less digits than its factorization.

21120323221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 438659.

The product of its (nonzero) digits is 288, while the sum is 19.

Adding to 21120323221 its reverse (12232302112), we get a palindrome (33352625333).

The spelling of 21120323221 in words is "twenty-one billion, one hundred twenty million, three hundred twenty-three thousand, two hundred twenty-one".