66155720863 has 8 divisors (see below), whose sum is σ = 67582266048. Its totient is φ = 64729966464.

The previous prime is 66155720861. The next prime is 66155720879. The reversal of 66155720863 is 36802755166.

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 66155720863 - 2¹ = 66155720861 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 (66155720861) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 27006 + ... + 364747.

It is an arithmetic number, because the mean of its divisors is an integer number (8447783256).

Almost surely, 2^66155720863 is an apocalyptic number.

66155720863 is a deficient number, since it is larger than the sum of its proper divisors (1426545185).

66155720863 is a wasteful number, since it uses less digits than its factorization.

66155720863 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 395393.

The product of its (nonzero) digits is 1814400, while the sum is 49.

The spelling of 66155720863 in words is "sixty-six billion, one hundred fifty-five million, seven hundred twenty thousand, eight hundred sixty-three".