66125680069 has 12 divisors (see below), whose sum is σ = 70174797420. Its totient is φ = 62299212480.

The previous prime is 66125680021. The next prime is 66125680099. The reversal of 66125680069 is 96008652166.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 1323868225 + 64801811844 = 36385^2 + 254562^2 .

It is not a de Polignac number, because 66125680069 - 2⁷ = 66125679941 is a prime.

It is a super-2 number, since 2×66125680069² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66125680099) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 440664 + ... + 571345.

It is an arithmetic number, because the mean of its divisors is an integer number (5847899785).

Almost surely, 2^66125680069 is an apocalyptic number.

It is an amenable number.

66125680069 is a deficient number, since it is larger than the sum of its proper divisors (4049117351).

66125680069 is a wasteful number, since it uses less digits than its factorization.

66125680069 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1012228 (or 1012209 counting only the distinct ones).

The product of its (nonzero) digits is 933120, while the sum is 49.

The spelling of 66125680069 in words is "sixty-six billion, one hundred twenty-five million, six hundred eighty thousand, sixty-nine".