66260726661 has 4 divisors (see below), whose sum is σ = 88347635552. Its totient is φ = 44173817772.

The previous prime is 66260726639. The next prime is 66260726671. The reversal of 66260726661 is 16662706266.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 66260726661 - 2⁵ = 66260726629 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 66260726661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66260726671) 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, 11043454441 + ... + 11043454446.

It is an arithmetic number, because the mean of its divisors is an integer number (22086908888).

Almost surely, 2^66260726661 is an apocalyptic number.

It is an amenable number.

66260726661 is a deficient number, since it is larger than the sum of its proper divisors (22086908891).

66260726661 is a wasteful number, since it uses less digits than its factorization.

66260726661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22086908890.

The product of its (nonzero) digits is 1306368, while the sum is 48.

The spelling of 66260726661 in words is "sixty-six billion, two hundred sixty million, seven hundred twenty-six thousand, six hundred sixty-one".