66155166505 has 8 divisors (see below), whose sum is σ = 79387819272. Its totient is φ = 52923053568.

The previous prime is 66155166487. The next prime is 66155166529. The reversal of 66155166505 is 50566155166.

It can be written as a sum of positive squares in 4 ways, for example, as 6390563481 + 59764603024 = 79941^2 + 244468^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 66155166505 - 2³¹ = 64007682857 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 219097 + ... + 424633.

It is an arithmetic number, because the mean of its divisors is an integer number (9923477409).

Almost surely, 2^66155166505 is an apocalyptic number.

It is an amenable number.

66155166505 is a deficient number, since it is larger than the sum of its proper divisors (13232652767).

66155166505 is a wasteful number, since it uses less digits than its factorization.

66155166505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 269915.

The product of its (nonzero) digits is 810000, while the sum is 46.

The spelling of 66155166505 in words is "sixty-six billion, one hundred fifty-five million, one hundred sixty-six thousand, five hundred five".