165221593 has 2 divisors, whose sum is σ = 165221594. Its totient is φ = 165221592.

The previous prime is 165221569. The next prime is 165221603. The reversal of 165221593 is 395122561.

165221593 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 87834384 + 77387209 = 9372^2 + 8797^2 .

It is a cyclic number.

It is not a de Polignac number, because 165221593 - 2⁵ = 165221561 is a prime.

It is not a weakly prime, because it can be changed into another prime (165221533) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82610796 + 82610797.

It is an arithmetic number, because the mean of its divisors is an integer number (82610797).

Almost surely, 2^165221593 is an apocalyptic number.

It is an amenable number.

165221593 is a deficient number, since it is larger than the sum of its proper divisors (1).

165221593 is an equidigital number, since it uses as much as digits as its factorization.

165221593 is an evil number, because the sum of its binary digits is even.

The product of its digits is 16200, while the sum is 34.

The square root of 165221593 is about 12853.8551804507. The cubic root of 165221593 is about 548.7260796993.

The spelling of 165221593 in words is "one hundred sixty-five million, two hundred twenty-one thousand, five hundred ninety-three".