20221213 has 2 divisors, whose sum is σ = 20221214. Its totient is φ = 20221212.

The previous prime is 20221193. The next prime is 20221231. The reversal of 20221213 is 31212202.

Together with next prime (20221231) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13860729 + 6360484 = 3723^2 + 2522^2 .

It is a cyclic number.

It is not a de Polignac number, because 20221213 - 2²¹ = 18124061 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20221193 and 20221202.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20221273) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10110606 + 10110607.

It is an arithmetic number, because the mean of its divisors is an integer number (10110607).

Almost surely, 2^20221213 is an apocalyptic number.

It is an amenable number.

20221213 is a deficient number, since it is larger than the sum of its proper divisors (1).

20221213 is an equidigital number, since it uses as much as digits as its factorization.

20221213 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 48, while the sum is 13.

The square root of 20221213 is about 4496.8003068849. The cubic root of 20221213 is about 272.4388685360.

Adding to 20221213 its reverse (31212202), we get a palindrome (51433415).

The spelling of 20221213 in words is "twenty million, two hundred twenty-one thousand, two hundred thirteen".