165211331 has 2 divisors, whose sum is σ = 165211332. Its totient is φ = 165211330.

The previous prime is 165211313. The next prime is 165211339. The reversal of 165211331 is 133112561.

Together with previous prime (165211313) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-165211331 is a prime.

It is a super-2 number, since 2×165211331² = 54589567781583122, which contains 22 as substring.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 165211297 and 165211306.

It is not a weakly prime, because it can be changed into another prime (165211339) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82605665 + 82605666.

It is an arithmetic number, because the mean of its divisors is an integer number (82605666).

Almost surely, 2^165211331 is an apocalyptic number.

165211331 is a deficient number, since it is larger than the sum of its proper divisors (1).

165211331 is an equidigital number, since it uses as much as digits as its factorization.

165211331 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 540, while the sum is 23.

The square root of 165211331 is about 12853.4559944009. The cubic root of 165211331 is about 548.7147189089.

Adding to 165211331 its reverse (133112561), we get a palindrome (298323892).

The spelling of 165211331 in words is "one hundred sixty-five million, two hundred eleven thousand, three hundred thirty-one".