65621617 has 2 divisors, whose sum is σ = 65621618. Its totient is φ = 65621616.

The previous prime is 65621603. The next prime is 65621627. The reversal of 65621617 is 71612656.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 46226401 + 19395216 = 6799^2 + 4404^2 .

It is a cyclic number.

It is not a de Polignac number, because 65621617 - 2⁷ = 65621489 is a prime.

It is equal to p_3875083 and since 65621617 and 3875083 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (65621627) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32810808 + 32810809.

It is an arithmetic number, because the mean of its divisors is an integer number (32810809).

Almost surely, 2^65621617 is an apocalyptic number.

It is an amenable number.

65621617 is a deficient number, since it is larger than the sum of its proper divisors (1).

65621617 is an equidigital number, since it uses as much as digits as its factorization.

65621617 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15120, while the sum is 34.

The square root of 65621617 is about 8100.7170670256. The cubic root of 65621617 is about 403.3502303024.

The spelling of 65621617 in words is "sixty-five million, six hundred twenty-one thousand, six hundred seventeen".