201643265 has 4 divisors (see below), whose sum is σ = 241971924. Its totient is φ = 161314608.

The previous prime is 201643261. The next prime is 201643327. The reversal of 201643265 is 562346102.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 562346102 = 2 ⋅281173051.

It can be written as a sum of positive squares in 2 ways, for example, as 106853569 + 94789696 = 10337^2 + 9736^2 .

It is a cyclic number.

It is not a de Polignac number, because 201643265 - 2² = 201643261 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (201643261) 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, 20164322 + ... + 20164331.

It is an arithmetic number, because the mean of its divisors is an integer number (60492981).

Almost surely, 2^201643265 is an apocalyptic number.

It is an amenable number.

201643265 is a deficient number, since it is larger than the sum of its proper divisors (40328659).

201643265 is an equidigital number, since it uses as much as digits as its factorization.

201643265 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40328658.

The product of its (nonzero) digits is 8640, while the sum is 29.

The square root of 201643265 is about 14200.1149643234. The cubic root of 201643265 is about 586.4008263465.

Adding to 201643265 its reverse (562346102), we get a palindrome (763989367).

The spelling of 201643265 in words is "two hundred one million, six hundred forty-three thousand, two hundred sixty-five".