165523201 has 4 divisors (see below), whose sum is σ = 165566212. Its totient is φ = 165480192.

The previous prime is 165523199. The next prime is 165523243. The reversal of 165523201 is 102325561.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 102325561 = 13 ⋅7871197.

It can be written as a sum of positive squares in 2 ways, for example, as 28633201 + 136890000 = 5351^2 + 11700^2 .

It is a cyclic number.

It is not a de Polignac number, because 165523201 - 2¹ = 165523199 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (165623201) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15096 + ... + 23641.

It is an arithmetic number, because the mean of its divisors is an integer number (41391553).

Almost surely, 2^165523201 is an apocalyptic number.

It is an amenable number.

165523201 is a deficient number, since it is larger than the sum of its proper divisors (43011).

165523201 is an equidigital number, since it uses as much as digits as its factorization.

165523201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43010.

The product of its (nonzero) digits is 1800, while the sum is 25.

The square root of 165523201 is about 12865.5820311403. The cubic root of 165523201 is about 549.0597721038.

Adding to 165523201 its reverse (102325561), we get a palindrome (267848762).

The spelling of 165523201 in words is "one hundred sixty-five million, five hundred twenty-three thousand, two hundred one".