66463343311661 has 4 divisors (see below), whose sum is σ = 66477140979612. Its totient is φ = 66449545643712.

The previous prime is 66463343311657. The next prime is 66463343311691. The reversal of 66463343311661 is 16611334336466.

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 14588503860100 + 51874839451561 = 3819490^2 + 7202419^2 .

It is a cyclic number.

It is not a de Polignac number, because 66463343311661 - 2² = 66463343311657 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66463343311691) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (31) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6898826750 + ... + 6898836383.

It is an arithmetic number, because the mean of its divisors is an integer number (16619285244903).

Almost surely, 2^{66463343311661} is an apocalyptic number.

It is an amenable number.

66463343311661 is a deficient number, since it is larger than the sum of its proper divisors (13797667951).

66463343311661 is a wasteful number, since it uses less digits than its factorization.

66463343311661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13797667950.

The product of its digits is 10077696, while the sum is 53.

The spelling of 66463343311661 in words is "sixty-six trillion, four hundred sixty-three billion, three hundred forty-three million, three hundred eleven thousand, six hundred sixty-one".