65811243 has 4 divisors (see below), whose sum is σ = 87748328. Its totient is φ = 43874160.

The previous prime is 65811241. The next prime is 65811259. The reversal of 65811243 is 34211856.

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

It is not a de Polignac number, because 65811243 - 2¹ = 65811241 is a prime.

It is a super-2 number, since 2×65811243² = 8662239410410098, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 65811243.

It is not an unprimeable number, because it can be changed into a prime (65811241) 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, 10968538 + ... + 10968543.

It is an arithmetic number, because the mean of its divisors is an integer number (21937082).

Almost surely, 2^65811243 is an apocalyptic number.

65811243 is a deficient number, since it is larger than the sum of its proper divisors (21937085).

65811243 is a wasteful number, since it uses less digits than its factorization.

65811243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21937084.

The product of its digits is 5760, while the sum is 30.

The square root of 65811243 is about 8112.4128962966. The cubic root of 65811243 is about 403.7383754445.

The spelling of 65811243 in words is "sixty-five million, eight hundred eleven thousand, two hundred forty-three".