65661556560611 has 4 divisors (see below), whose sum is σ = 71630788975224. Its totient is φ = 59692324146000.

The previous prime is 65661556560599. The next prime is 65661556560647. The reversal of 65661556560611 is 11606565516656.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-65661556560611 is a prime.

It is a super-2 number, since 2×65661556560611² (a number of 28 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (65661556566611) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2984616207290 + ... + 2984616207311.

It is an arithmetic number, because the mean of its divisors is an integer number (17907697243806).

Almost surely, 2^{65661556560611} is an apocalyptic number.

65661556560611 is a deficient number, since it is larger than the sum of its proper divisors (5969232414613).

65661556560611 is a wasteful number, since it uses less digits than its factorization.

65661556560611 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5969232414612.

The product of its (nonzero) digits is 29160000, while the sum is 59.

The spelling of 65661556560611 in words is "sixty-five trillion, six hundred sixty-one billion, five hundred fifty-six million, five hundred sixty thousand, six hundred eleven".