65421623569 has 2 divisors, whose sum is σ = 65421623570. Its totient is φ = 65421623568.

The previous prime is 65421623513. The next prime is 65421623627. The reversal of 65421623569 is 96532612456.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 61398892944 + 4022730625 = 247788^2 + 63425^2 .

It is a cyclic number.

It is not a de Polignac number, because 65421623569 - 2¹³ = 65421615377 is a prime.

It is a super-2 number, since 2×65421623569² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (65421633569) 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 as a sum of consecutive naturals, namely, 32710811784 + 32710811785.

It is an arithmetic number, because the mean of its divisors is an integer number (32710811785).

Almost surely, 2^65421623569 is an apocalyptic number.

It is an amenable number.

65421623569 is a deficient number, since it is larger than the sum of its proper divisors (1).

65421623569 is an equidigital number, since it uses as much as digits as its factorization.

65421623569 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2332800, while the sum is 49.

The spelling of 65421623569 in words is "sixty-five billion, four hundred twenty-one million, six hundred twenty-three thousand, five hundred sixty-nine".