165214909 has 2 divisors, whose sum is σ = 165214910. Its totient is φ = 165214908.

The previous prime is 165214843. The next prime is 165214919. The reversal of 165214909 is 909412561.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 128187684 + 37027225 = 11322^2 + 6085^2 .

It is a cyclic number.

It is not a de Polignac number, because 165214909 - 2¹⁵ = 165182141 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (165214919) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82607454 + 82607455.

It is an arithmetic number, because the mean of its divisors is an integer number (82607455).

Almost surely, 2^165214909 is an apocalyptic number.

It is an amenable number.

165214909 is a deficient number, since it is larger than the sum of its proper divisors (1).

165214909 is an equidigital number, since it uses as much as digits as its factorization.

165214909 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 19440, while the sum is 37.

The square root of 165214909 is about 12853.5951780037. The cubic root of 165214909 is about 548.7186800721.

It can be divided in two parts, 1652 and 14909, that added together give a palindrome (16561).

The spelling of 165214909 in words is "one hundred sixty-five million, two hundred fourteen thousand, nine hundred nine".