165391871 has 2 divisors, whose sum is σ = 165391872. Its totient is φ = 165391870.

The previous prime is 165391847. The next prime is 165391907. The reversal of 165391871 is 178193561.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 165391871 - 2¹⁰ = 165390847 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (165390871) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82695935 + 82695936.

It is an arithmetic number, because the mean of its divisors is an integer number (82695936).

Almost surely, 2^165391871 is an apocalyptic number.

165391871 is a deficient number, since it is larger than the sum of its proper divisors (1).

165391871 is an equidigital number, since it uses as much as digits as its factorization.

165391871 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 45360, while the sum is 41.

The square root of 165391871 is about 12860.4770906837. The cubic root of 165391871 is about 548.9145213704.

The spelling of 165391871 in words is "one hundred sixty-five million, three hundred ninety-one thousand, eight hundred seventy-one".