4243520065 has 4 divisors (see below), whose sum is σ = 5092224084. Its totient is φ = 3394816048.

The previous prime is 4243520053. The next prime is 4243520069. The reversal of 4243520065 is 5600253424.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2170721281 + 2072798784 = 46591^2 + 45528^2 .

It is a cyclic number.

It is not a de Polignac number, because 4243520065 - 2¹⁹ = 4242995777 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (4243520069) 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, 424352002 + ... + 424352011.

It is an arithmetic number, because the mean of its divisors is an integer number (1273056021).

Almost surely, 2^4243520065 is an apocalyptic number.

It is an amenable number.

4243520065 is a deficient number, since it is larger than the sum of its proper divisors (848704019).

4243520065 is an equidigital number, since it uses as much as digits as its factorization.

4243520065 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 848704018.

The product of its (nonzero) digits is 28800, while the sum is 31.

The square root of 4243520065 is about 65142.3062609853. The cubic root of 4243520065 is about 1618.9822476210.

Adding to 4243520065 its reverse (5600253424), we get a palindrome (9843773489).

It can be divided in two parts, 42435 and 20065, that added together give a square (62500 = 250²).

The spelling of 4243520065 in words is "four billion, two hundred forty-three million, five hundred twenty thousand, sixty-five".