165986441 has 2 divisors, whose sum is σ = 165986442. Its totient is φ = 165986440.

The previous prime is 165986437. The next prime is 165986473. The reversal of 165986441 is 144689561.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 165379600 + 606841 = 12860^2 + 779^2 .

It is a cyclic number.

It is not a de Polignac number, because 165986441 - 2² = 165986437 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 165986392 and 165986401.

It is not a weakly prime, because it can be changed into another prime (165986141) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82993220 + 82993221.

It is an arithmetic number, because the mean of its divisors is an integer number (82993221).

Almost surely, 2^165986441 is an apocalyptic number.

It is an amenable number.

165986441 is a deficient number, since it is larger than the sum of its proper divisors (1).

165986441 is an equidigital number, since it uses as much as digits as its factorization.

165986441 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 207360, while the sum is 44.

The square root of 165986441 is about 12883.5725247309. The cubic root of 165986441 is about 549.5715020621.

The spelling of 165986441 in words is "one hundred sixty-five million, nine hundred eighty-six thousand, four hundred forty-one".