64811953684665 has 36 divisors (see below), whose sum is σ = 123481948132452. Its totient is φ = 31423977541440.

The previous prime is 64811953684657. The next prime is 64811953684721. The reversal of 64811953684665 is 56648635911846.

It is a happy number.

64811953684665 is a `hidden beast` number, since 6 + 4 + 8 + 1 + 1 + 9 + 536 + 84 + 6 + 6 + 5 = 666.

64811953684665 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 24378837125049 + 40433116559616 = 4937493^2 + 6358704^2 .

It is not a de Polignac number, because 64811953684665 - 2³ = 64811953684657 is a prime.

It is a super-2 number, since 2×64811953684665² (a number of 28 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 64811953684593 and 64811953684602.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 5951505454 + ... + 5951516343.

Almost surely, 2^{64811953684665} is an apocalyptic number.

It is an amenable number.

64811953684665 is a deficient number, since it is larger than the sum of its proper divisors (58669994447787).

64811953684665 is a wasteful number, since it uses less digits than its factorization.

64811953684665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11903021830 (or 11903021816 counting only the distinct ones).

The product of its digits is 895795200, while the sum is 72.

The spelling of 64811953684665 in words is "sixty-four trillion, eight hundred eleven billion, nine hundred fifty-three million, six hundred eighty-four thousand, six hundred sixty-five".