165515563 has 2 divisors, whose sum is σ = 165515564. Its totient is φ = 165515562.

The previous prime is 165515561. The next prime is 165515569. The reversal of 165515563 is 365515561.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 165515563 - 2¹ = 165515561 is a prime.

Together with 165515561, it forms a pair of twin primes.

It is equal to p_9266176 and since 165515563 and 9266176 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (165515561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82757781 + 82757782.

It is an arithmetic number, because the mean of its divisors is an integer number (82757782).

Almost surely, 2^165515563 is an apocalyptic number.

165515563 is a deficient number, since it is larger than the sum of its proper divisors (1).

165515563 is an equidigital number, since it uses as much as digits as its factorization.

165515563 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 67500, while the sum is 37.

The square root of 165515563 is about 12865.2851892214. The cubic root of 165515563 is about 549.0513265948.

The spelling of 165515563 in words is "one hundred sixty-five million, five hundred fifteen thousand, five hundred sixty-three".