65011221 has 32 divisors (see below), whose sum is σ = 106583040. Its totient is φ = 38833200.

The previous prime is 65011201. The next prime is 65011223. The reversal of 65011221 is 12211056.

65011221 is a `hidden beast` number, since 650 + 1 + 12 + 2 + 1 = 666.

It is not a de Polignac number, because 65011221 - 2⁶ = 65011157 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 65011194 and 65011203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65011223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 19546 + ... + 22628.

It is an arithmetic number, because the mean of its divisors is an integer number (3330720).

Almost surely, 2^65011221 is an apocalyptic number.

It is an amenable number.

65011221 is a deficient number, since it is larger than the sum of its proper divisors (41571819).

65011221 is a wasteful number, since it uses less digits than its factorization.

65011221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3174 (or 3168 counting only the distinct ones).

The product of its (nonzero) digits is 120, while the sum is 18.

The square root of 65011221 is about 8062.9536151463. The cubic root of 65011221 is about 402.0957112270.

Adding to 65011221 its reverse (12211056), we get a palindrome (77222277).

The spelling of 65011221 in words is "sixty-five million, eleven thousand, two hundred twenty-one".