21222321232381 has 2 divisors, whose sum is σ = 21222321232382. Its totient is φ = 21222321232380.

The previous prime is 21222321232373. The next prime is 21222321232433. The reversal of 21222321232381 is 18323212322212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16998716702500 + 4223604529881 = 4122950^2 + 2055141^2 .

It is a cyclic number.

It is not a de Polignac number, because 21222321232381 - 2³ = 21222321232373 is a prime.

It is a super-2 number, since 2×21222321232381² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21222301232381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10611160616190 + 10611160616191.

It is an arithmetic number, because the mean of its divisors is an integer number (10611160616191).

Almost surely, 2^{21222321232381} is an apocalyptic number.

It is an amenable number.

21222321232381 is a deficient number, since it is larger than the sum of its proper divisors (1).

21222321232381 is an equidigital number, since it uses as much as digits as its factorization.

21222321232381 is an evil number, because the sum of its binary digits is even.

The product of its digits is 27648, while the sum is 34.

Adding to 21222321232381 its reverse (18323212322212), we get a palindrome (39545533554593).

The spelling of 21222321232381 in words is "twenty-one trillion, two hundred twenty-two billion, three hundred twenty-one million, two hundred thirty-two thousand, three hundred eighty-one".