158918321 has 2 divisors, whose sum is σ = 158918322. Its totient is φ = 158918320.

The previous prime is 158918297. The next prime is 158918351. The reversal of 158918321 is 123819851.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 154654096 + 4264225 = 12436^2 + 2065^2 .

It is an emirp because it is prime and its reverse (123819851) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-158918321 is a prime.

It is a super-3 number, since 3×158918321³ (a number of 26 digits) contains 333 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (158918351) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 79459160 + 79459161.

It is an arithmetic number, because the mean of its divisors is an integer number (79459161).

Almost surely, 2^158918321 is an apocalyptic number.

It is an amenable number.

158918321 is a deficient number, since it is larger than the sum of its proper divisors (1).

158918321 is an equidigital number, since it uses as much as digits as its factorization.

158918321 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 17280, while the sum is 38.

The square root of 158918321 is about 12606.2810138439. The cubic root of 158918321 is about 541.6573691290.

The spelling of 158918321 in words is "one hundred fifty-eight million, nine hundred eighteen thousand, three hundred twenty-one".