65653720505 has 4 divisors (see below), whose sum is σ = 78784464612. Its totient is φ = 52522976400.

The previous prime is 65653720493. The next prime is 65653720607. The reversal of 65653720505 is 50502735656.

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 46209091369 + 19444629136 = 214963^2 + 139444^2 .

It is not a de Polignac number, because 65653720505 - 2¹² = 65653716409 is a prime.

It is a super-2 number, since 2×65653720505² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6565372046 + ... + 6565372055.

It is an arithmetic number, because the mean of its divisors is an integer number (19696116153).

Almost surely, 2^65653720505 is an apocalyptic number.

It is an amenable number.

65653720505 is a deficient number, since it is larger than the sum of its proper divisors (13130744107).

65653720505 is a wasteful number, since it uses less digits than its factorization.

65653720505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13130744106.

The product of its (nonzero) digits is 945000, while the sum is 44.

The spelling of 65653720505 in words is "sixty-five billion, six hundred fifty-three million, seven hundred twenty thousand, five hundred five".