165415949 has 2 divisors, whose sum is σ = 165415950. Its totient is φ = 165415948.

The previous prime is 165415909. The next prime is 165415951. The reversal of 165415949 is 949514561.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 142038724 + 23377225 = 11918^2 + 4835^2 .

It is an emirp because it is prime and its reverse (949514561) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 165415949 - 2¹⁶ = 165350413 is a prime.

It is a Sophie Germain prime.

Together with 165415951, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (165415909) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82707974 + 82707975.

It is an arithmetic number, because the mean of its divisors is an integer number (82707975).

Almost surely, 2^165415949 is an apocalyptic number.

It is an amenable number.

165415949 is a deficient number, since it is larger than the sum of its proper divisors (1).

165415949 is an equidigital number, since it uses as much as digits as its factorization.

165415949 is an evil number, because the sum of its binary digits is even.

The product of its digits is 194400, while the sum is 44.

The square root of 165415949 is about 12861.4131805179. The cubic root of 165415949 is about 548.9411573480.

The spelling of 165415949 in words is "one hundred sixty-five million, four hundred fifteen thousand, nine hundred forty-nine".