143221021 has 2 divisors, whose sum is σ = 143221022. Its totient is φ = 143221020.

The previous prime is 143220997. The next prime is 143221027. The reversal of 143221021 is 120122341.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 74563225 + 68657796 = 8635^2 + 8286^2 .

It is an emirp because it is prime and its reverse (120122341) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-143221021 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 143220986 and 143221004.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (143221027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 71610510 + 71610511.

It is an arithmetic number, because the mean of its divisors is an integer number (71610511).

Almost surely, 2^143221021 is an apocalyptic number.

It is an amenable number.

143221021 is a deficient number, since it is larger than the sum of its proper divisors (1).

143221021 is an equidigital number, since it uses as much as digits as its factorization.

143221021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 96, while the sum is 16.

The square root of 143221021 is about 11967.4985272612. The cubic root of 143221021 is about 523.2014293811.

Adding to 143221021 its reverse (120122341), we get a palindrome (263343362).

The spelling of 143221021 in words is "one hundred forty-three million, two hundred twenty-one thousand, twenty-one".