165221326 has 4 divisors (see below), whose sum is σ = 247831992. Its totient is φ = 82610662.

The previous prime is 165221293. The next prime is 165221333. The reversal of 165221326 is 623122561.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 623122561 = 18061 ⋅34501.

It is a junction number, because it is equal to n+sod(n) for n = 165221294 and 165221303.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41305330 + ... + 41305333.

It is an arithmetic number, because the mean of its divisors is an integer number (61957998).

Almost surely, 2^165221326 is an apocalyptic number.

165221326 is a deficient number, since it is larger than the sum of its proper divisors (82610666).

165221326 is an equidigital number, since it uses as much as digits as its factorization.

165221326 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82610665.

The product of its digits is 4320, while the sum is 28.

The square root of 165221326 is about 12853.8447944574. The cubic root of 165221326 is about 548.7257841165.

Adding to 165221326 its reverse (623122561), we get a palindrome (788343887).

The spelling of 165221326 in words is "one hundred sixty-five million, two hundred twenty-one thousand, three hundred twenty-six".