21223331671 has 2 divisors, whose sum is σ = 21223331672. Its totient is φ = 21223331670.

The previous prime is 21223331663. The next prime is 21223331681. The reversal of 21223331671 is 17613332212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21223331671 - 2³ = 21223331663 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21223331611) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10611665835 + 10611665836.

It is an arithmetic number, because the mean of its divisors is an integer number (10611665836).

Almost surely, 2^21223331671 is an apocalyptic number.

21223331671 is a deficient number, since it is larger than the sum of its proper divisors (1).

21223331671 is an equidigital number, since it uses as much as digits as its factorization.

21223331671 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9072, while the sum is 31.

Adding to 21223331671 its reverse (17613332212), we get a palindrome (38836663883).

The spelling of 21223331671 in words is "twenty-one billion, two hundred twenty-three million, three hundred thirty-one thousand, six hundred seventy-one".