66506244511 has 4 divisors (see below), whose sum is σ = 76007136592. Its totient is φ = 57005352432.

The previous prime is 66506244487. The next prime is 66506244523. The reversal of 66506244511 is 11544260566.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 11544260566 = 2 ⋅5772130283.

It is a de Polignac number, because none of the positive numbers 2^k-66506244511 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 (66506244911) 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, 4750446030 + ... + 4750446043.

It is an arithmetic number, because the mean of its divisors is an integer number (19001784148).

Almost surely, 2^66506244511 is an apocalyptic number.

66506244511 is a deficient number, since it is larger than the sum of its proper divisors (9500892081).

66506244511 is an equidigital number, since it uses as much as digits as its factorization.

66506244511 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9500892080.

The product of its (nonzero) digits is 172800, while the sum is 40.

The spelling of 66506244511 in words is "sixty-six billion, five hundred six million, two hundred forty-four thousand, five hundred eleven".