146243221 has 2 divisors, whose sum is σ = 146243222. Its totient is φ = 146243220.

The previous prime is 146243219. The next prime is 146243233. The reversal of 146243221 is 122342641.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 143400625 + 2842596 = 11975^2 + 1686^2 .

It is an emirp because it is prime and its reverse (122342641) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 146243221 - 2¹ = 146243219 is a prime.

Together with 146243219, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (146243621) 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, 73121610 + 73121611.

It is an arithmetic number, because the mean of its divisors is an integer number (73121611).

Almost surely, 2^146243221 is an apocalyptic number.

It is an amenable number.

146243221 is a deficient number, since it is larger than the sum of its proper divisors (1).

146243221 is an equidigital number, since it uses as much as digits as its factorization.

146243221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2304, while the sum is 25.

The square root of 146243221 is about 12093.1063420446. The cubic root of 146243221 is about 526.8559809631.

Adding to 146243221 its reverse (122342641), we get a palindrome (268585862).

The spelling of 146243221 in words is "one hundred forty-six million, two hundred forty-three thousand, two hundred twenty-one".