66717644012251 has 8 divisors (see below), whose sum is σ = 67396979948544. Its totient is φ = 66039867976320.

The previous prime is 66717644012207. The next prime is 66717644012359. The reversal of 66717644012251 is 15221044671766.

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 66717644012251 - 2¹¹ = 66717644010203 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66717648012251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 389889115 + ... + 390060196.

It is an arithmetic number, because the mean of its divisors is an integer number (8424622493568).

Almost surely, 2^{66717644012251} is an apocalyptic number.

66717644012251 is a deficient number, since it is larger than the sum of its proper divisors (679335936293).

66717644012251 is a wasteful number, since it uses less digits than its factorization.

66717644012251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 779950181.

The product of its (nonzero) digits is 3386880, while the sum is 52.

The spelling of 66717644012251 in words is "sixty-six trillion, seven hundred seventeen billion, six hundred forty-four million, twelve thousand, two hundred fifty-one".