162820321 has 2 divisors, whose sum is σ = 162820322. Its totient is φ = 162820320.

The previous prime is 162820283. The next prime is 162820331. The reversal of 162820321 is 123028261.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 146531025 + 16289296 = 12105^2 + 4036^2 .

It is an emirp because it is prime and its reverse (123028261) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 162820321 - 2⁹ = 162819809 is a prime.

It is not a weakly prime, because it can be changed into another prime (162820331) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 81410160 + 81410161.

It is an arithmetic number, because the mean of its divisors is an integer number (81410161).

Almost surely, 2^162820321 is an apocalyptic number.

It is an amenable number.

162820321 is a deficient number, since it is larger than the sum of its proper divisors (1).

162820321 is an equidigital number, since it uses as much as digits as its factorization.

162820321 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1152, while the sum is 25.

The square root of 162820321 is about 12760.1066218116. The cubic root of 162820321 is about 546.0547662508.

Adding to 162820321 its reverse (123028261), we get a palindrome (285848582).

The spelling of 162820321 in words is "one hundred sixty-two million, eight hundred twenty thousand, three hundred twenty-one".