20321003131221 has 32 divisors (see below), whose sum is σ = 29447206629120. Its totient is φ = 12390310001664.

The previous prime is 20321003131193. The next prime is 20321003131237. The reversal of 20321003131221 is 12213130012302.

It is not a de Polignac number, because 20321003131221 - 2¹⁷ = 20321003000149 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20321003131621) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 12064840 + ... + 13645598.

It is an arithmetic number, because the mean of its divisors is an integer number (920225207160).

Almost surely, 2^{20321003131221} is an apocalyptic number.

It is an amenable number.

20321003131221 is a deficient number, since it is larger than the sum of its proper divisors (9126203497899).

20321003131221 is a wasteful number, since it uses less digits than its factorization.

20321003131221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1583805.

The product of its (nonzero) digits is 432, while the sum is 21.

Adding to 20321003131221 its reverse (12213130012302), we get a palindrome (32534133143523).

The spelling of 20321003131221 in words is "twenty trillion, three hundred twenty-one billion, three million, one hundred thirty-one thousand, two hundred twenty-one".