143221313 has 4 divisors (see below), whose sum is σ = 144535380. Its totient is φ = 141907248.

The previous prime is 143221303. The next prime is 143221349. The reversal of 143221313 is 313122341.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 313122341 = 7 ⋅44731763.

It can be written as a sum of positive squares in 2 ways, for example, as 41049649 + 102171664 = 6407^2 + 10108^2 .

It is a cyclic number.

It is not a de Polignac number, because 143221313 - 2¹⁰ = 143220289 is a prime.

It is a super-3 number, since 3×143221313³ (a number of 25 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (143221303) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 656870 + ... + 657087.

It is an arithmetic number, because the mean of its divisors is an integer number (36133845).

Almost surely, 2^143221313 is an apocalyptic number.

It is an amenable number.

143221313 is a deficient number, since it is larger than the sum of its proper divisors (1314067).

143221313 is a wasteful number, since it uses less digits than its factorization.

143221313 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1314066.

The product of its digits is 432, while the sum is 20.

The square root of 143221313 is about 11967.5107269641. The cubic root of 143221313 is about 523.2017849497.

Adding to 143221313 its reverse (313122341), we get a palindrome (456343654).

The spelling of 143221313 in words is "one hundred forty-three million, two hundred twenty-one thousand, three hundred thirteen".