20021322131221 has 2 divisors, whose sum is σ = 20021322131222. Its totient is φ = 20021322131220.

The previous prime is 20021322131191. The next prime is 20021322131257. The reversal of 20021322131221 is 12213122312002.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17521005356100 + 2500316775121 = 4185810^2 + 1581239^2 .

It is a cyclic number.

It is not a de Polignac number, because 20021322131221 - 2³¹ = 20019174647573 is a prime.

It is a super-3 number, since 3×20021322131221³ (a number of 41 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 20021322131192 and 20021322131201.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20021322137221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10010661065610 + 10010661065611.

It is an arithmetic number, because the mean of its divisors is an integer number (10010661065611).

Almost surely, 2^{20021322131221} is an apocalyptic number.

It is an amenable number.

20021322131221 is a deficient number, since it is larger than the sum of its proper divisors (1).

20021322131221 is an equidigital number, since it uses as much as digits as its factorization.

20021322131221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 576, while the sum is 22.

Adding to 20021322131221 its reverse (12213122312002), we get a palindrome (32234444443223).

The spelling of 20021322131221 in words is "twenty trillion, twenty-one billion, three hundred twenty-two million, one hundred thirty-one thousand, two hundred twenty-one".