165135281 has 2 divisors, whose sum is σ = 165135282. Its totient is φ = 165135280.

The previous prime is 165135259. The next prime is 165135301. The reversal of 165135281 is 182531561.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 152744881 + 12390400 = 12359^2 + 3520^2 .

It is an emirp because it is prime and its reverse (182531561) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 165135281 - 2²⁶ = 98026417 is a prime.

It is a super-2 number, since 2×165135281² = 54539322061897922, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (165135241) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82567640 + 82567641.

It is an arithmetic number, because the mean of its divisors is an integer number (82567641).

Almost surely, 2^165135281 is an apocalyptic number.

It is an amenable number.

165135281 is a deficient number, since it is larger than the sum of its proper divisors (1).

165135281 is an equidigital number, since it uses as much as digits as its factorization.

165135281 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7200, while the sum is 32.

The square root of 165135281 is about 12850.4973055520. The cubic root of 165135281 is about 548.6305112888.

The spelling of 165135281 in words is "one hundred sixty-five million, one hundred thirty-five thousand, two hundred eighty-one".